Season 4 (The Flash)

The fourth season of ​​​ premiered on October 10, 2017, on The CW and concluded on May 22, 2018. The season consisted of 23 episodes.
==Synopsis==
==Cast==
===Main cast===
*Grant Gustin as Barry Allen/The Flash
*Candice Patton as Iris West-Allen
*Danielle Panabaker as Dr. Caitlin Snow/Killer Frost
*Carlos Valdes as Cisco Ramon/Vibe
*Keiynan Lonsdale as Wally West/Kid Flash
*Neil Sandilands as Professor Clifford DeVoe/The Thinker
*Tom Cavanagh as Dr. Harrison "Harry" Wells, Dr. Harrison Wolfgang Wells, H. Lothario Wells, Wells 2.0, Wells the Grey, Professor Eobard Thawne/Reverse-Flash, Sonny Wells, and H.P. Wells
*Jesse L. Martin as Detective Joe West
===Recurring cast===
*Danielle Nicolet as District Attorney Cecile Horton
*Mark Sweatman as Matthew Norvock
*Kim Engelbrecht as Dr. Marlize DeVoe
*Dominic Burgess as Ramsey Deacon/Kilg%re
*Patrick Sabongui as Captain David Singh
*Jessica Camacho as Cynthia/Gypsy
*Donna Pescow as Dr. Sharon Finkel
*Richard Brooks as Warden Gregory Wolfe
*Sugar Lyn Beard as Becky Sharpe/Hazard and Professor Clifford DeVoe/The Thinker
*Danny Trejo as Josh/Breacher
*Hartley Sawyer as Ralph Dibny/Elongated Man and Professor Clifford DeVoe
*Katee Sackhoff as Leslie Jocoy/Amunet Black
*Chelsea Kurtz as Mina Chaytan/Black Bison
*Kendrick Sampson as Dominic Lanse/Brainstorm and Professor Clifford DeVoe/The Thinker
*Ryan Alexander McDonald as Neil Borman/Fallout
*Bill Goldberg as David Ratchet
*Jessica Parker Kennedy as Nora West-Allen/XS
*Derek Mears as Sylbert Rundine/Dwarfstar
*Paul McGillion as Earl Cox
*Miranda MacDougall as Izzy Bowin/The Fiddler and Professor Clifford DeVoe/The Thinker
*Leonardo Nam as Matthew Kim/Melting Point
*Bethany Brown as Janet Petty/Null
*Arturo del Puerto as Edwin Gauss/Folded Man and Professor Clifford DeVoe
==Episodes==
1 	 	Glen Winter 	Andrew Kreisberg 	Todd Helbing & Eric Wallace 	October 10, 2017
With Barry in the speed force, Iris, Kid Flash, Joe and Vibe have taken over protecting Central City. However, when a powerful armored villain threatens to level the city if The Flash doesn't appear, Cisco makes a risky decision to break Barry out of the speed force. However, the Barry that comes out isn't the same Barry that went in. 	With Barry in the speed force, Iris, Kid Flash, Joe and Vibe have taken over protecting Central City. However, when a powerful armored villain threatens to level the city if The Flash doesn't appear, Cisco makes a risky decision to break Barry out of the speed force. However, the Barry that comes out isn't the same Barry that went in. 	With Barry in the speed force, Iris, Kid Flash, Joe and Vibe have taken over protecting Central City. However, when a powerful armored villain threatens to level the city if The Flash doesn't appear, Cisco makes a risky decision to break Barry out of the speed force. However, the Barry that comes out isn't the same Barry that went in. 	With Barry in the speed force, Iris, Kid Flash, Joe and Vibe have taken over protecting Central City. However, when a powerful armored villain threatens to level the city if The Flash doesn't appear, Cisco makes a risky decision to break Barry out of the speed force. However, the Barry that comes out isn't the same Barry that went in. 	With Barry in the speed force, Iris, Kid Flash, Joe and Vibe have taken over protecting Central City. However, when a powerful armored villain threatens to level the city if The Flash doesn't appear, Cisco makes a risky decision to break Barry out of the speed force. However, the Barry that comes out isn't the same Barry that went in. 	With Barry in the speed force, Iris, Kid Flash, Joe and Vibe have taken over protecting Central City. However, when a powerful armored villain threatens to level the city if The Flash doesn't appear, Cisco makes a risky decision to break Barry out of the speed force. However, the Barry that comes out isn't the same Barry that went in.
2 	 	Alexandra La Roche 	Jonathan Butler & Gabriel Garza 	Jonathan Butler & Gabriel Garza 	October 17, 2017
Barry has his hands full when he takes on a dangerous meta who can control technology, while also confronting an obstacle in his personal life; the ramifications of abandoning Iris for six months to balance the Speed Force. Meanwhile, Gypsy breaches in for a hot date with Cisco, but she gets annoyed when his work keeps them apart. 	Barry has his hands full when he takes on a dangerous meta who can control technology, while also confronting an obstacle in his personal life; the ramifications of abandoning Iris for six months to balance the Speed Force. Meanwhile, Gypsy breaches in for a hot date with Cisco, but she gets annoyed when his work keeps them apart. 	Barry has his hands full when he takes on a dangerous meta who can control technology, while also confronting an obstacle in his personal life; the ramifications of abandoning Iris for six months to balance the Speed Force. Meanwhile, Gypsy breaches in for a hot date with Cisco, but she gets annoyed when his work keeps them apart. 	Barry has his hands full when he takes on a dangerous meta who can control technology, while also confronting an obstacle in his personal life; the ramifications of abandoning Iris for six months to balance the Speed Force. Meanwhile, Gypsy breaches in for a hot date with Cisco, but she gets annoyed when his work keeps them apart. 	Barry has his hands full when he takes on a dangerous meta who can control technology, while also confronting an obstacle in his personal life; the ramifications of abandoning Iris for six months to balance the Speed Force. Meanwhile, Gypsy breaches in for a hot date with Cisco, but she gets annoyed when his work keeps them apart. 	Barry has his hands full when he takes on a dangerous meta who can control technology, while also confronting an obstacle in his personal life; the ramifications of abandoning Iris for six months to balance the Speed Force. Meanwhile, Gypsy breaches in for a hot date with Cisco, but she gets annoyed when his work keeps them apart.
3 	 	Armen V. Kevorkian 	Sam Chalsen & Judalina Neira 	Sam Chalsen & Judalina Neira 	October 24, 2017
Barry and the team are hit by a string of bad luck and realize it is the handiwork of a new meta, Becky nicknamed Hazard, who has the ability to give others bad luck, while cashing in the benefits for herself. Meanwhile, Harry Wells returns to Earth-1 to give Wally a message from Jesse. 	Barry and the team are hit by a string of bad luck and realize it is the handiwork of a new meta, Becky nicknamed Hazard, who has the ability to give others bad luck, while cashing in the benefits for herself. Meanwhile, Harry Wells returns to Earth-1 to give Wally a message from Jesse. 	Barry and the team are hit by a string of bad luck and realize it is the handiwork of a new meta, Becky nicknamed Hazard, who has the ability to give others bad luck, while cashing in the benefits for herself. Meanwhile, Harry Wells returns to Earth-1 to give Wally a message from Jesse. 	Barry and the team are hit by a string of bad luck and realize it is the handiwork of a new meta, Becky nicknamed Hazard, who has the ability to give others bad luck, while cashing in the benefits for herself. Meanwhile, Harry Wells returns to Earth-1 to give Wally a message from Jesse. 	Barry and the team are hit by a string of bad luck and realize it is the handiwork of a new meta, Becky nicknamed Hazard, who has the ability to give others bad luck, while cashing in the benefits for herself. Meanwhile, Harry Wells returns to Earth-1 to give Wally a message from Jesse. 	Barry and the team are hit by a string of bad luck and realize it is the handiwork of a new meta, Becky nicknamed Hazard, who has the ability to give others bad luck, while cashing in the benefits for herself. Meanwhile, Harry Wells returns to Earth-1 to give Wally a message from Jesse.
4 	 	Tom Cavanagh 	Sterling Gates & Thomas Pound 	Sterling Gates & Thomas Pound 	October 31, 2017
Cisco is shocked when Gypsy's father, Breacher, shows up on Earth-1. Breacher takes an immediate disliking to Cisco and decides to hunt him. Meanwhile, Barry runs into his old nemesis, Ralph Dibny. 	Cisco is shocked when Gypsy's father, Breacher, shows up on Earth-1. Breacher takes an immediate disliking to Cisco and decides to hunt him. Meanwhile, Barry runs into his old nemesis, Ralph Dibny. 	Cisco is shocked when Gypsy's father, Breacher, shows up on Earth-1. Breacher takes an immediate disliking to Cisco and decides to hunt him. Meanwhile, Barry runs into his old nemesis, Ralph Dibny. 	Cisco is shocked when Gypsy's father, Breacher, shows up on Earth-1. Breacher takes an immediate disliking to Cisco and decides to hunt him. Meanwhile, Barry runs into his old nemesis, Ralph Dibny. 	Cisco is shocked when Gypsy's father, Breacher, shows up on Earth-1. Breacher takes an immediate disliking to Cisco and decides to hunt him. Meanwhile, Barry runs into his old nemesis, Ralph Dibny. 	Cisco is shocked when Gypsy's father, Breacher, shows up on Earth-1. Breacher takes an immediate disliking to Cisco and decides to hunt him. Meanwhile, Barry runs into his old nemesis, Ralph Dibny.
5 	 	Laura Belsey 	Lauren Certo & Kristen Kim 	Lauren Certo & Kristen Kim 	November 7, 2017
Having received an ominous threat from her old boss, Amunet, Caitlin fears that her past time as Killer Frost may be back to haunt her. Felicity comes to Central City to help the girls celebrate Iris's bachelorette party, while Cisco, Joe and the guys take Barry out for a night on the town. 	Having received an ominous threat from her old boss, Amunet, Caitlin fears that her past time as Killer Frost may be back to haunt her. Felicity comes to Central City to help the girls celebrate Iris's bachelorette party, while Cisco, Joe and the guys take Barry out for a night on the town. 	Having received an ominous threat from her old boss, Amunet, Caitlin fears that her past time as Killer Frost may be back to haunt her. Felicity comes to Central City to help the girls celebrate Iris's bachelorette party, while Cisco, Joe and the guys take Barry out for a night on the town. 	Having received an ominous threat from her old boss, Amunet, Caitlin fears that her past time as Killer Frost may be back to haunt her. Felicity comes to Central City to help the girls celebrate Iris's bachelorette party, while Cisco, Joe and the guys take Barry out for a night on the town. 	Having received an ominous threat from her old boss, Amunet, Caitlin fears that her past time as Killer Frost may be back to haunt her. Felicity comes to Central City to help the girls celebrate Iris's bachelorette party, while Cisco, Joe and the guys take Barry out for a night on the town. 	Having received an ominous threat from her old boss, Amunet, Caitlin fears that her past time as Killer Frost may be back to haunt her. Felicity comes to Central City to help the girls celebrate Iris's bachelorette party, while Cisco, Joe and the guys take Barry out for a night on the town.
6 	 	Brent Crowell 	Jonathan Butler & Gabriel Garza 	Jonathan Butler & Gabriel Garza 	November 14, 2017
When collectors of Native American artifacts are attacked by a meta named Mina Chayton who can bring inanimate objects to life, Barry turns to a surprising ally for help. Determined to crack the identity of The Thinker, Harry enlists Cisco’s help to summon the ultimate think tank; "The Council of Wells", a roundtable of the brightest Harrison Wells’ from various Earths. 	When collectors of Native American artifacts are attacked by a meta named Mina Chayton who can bring inanimate objects to life, Barry turns to a surprising ally for help. Determined to crack the identity of The Thinker, Harry enlists Cisco’s help to summon the ultimate think tank; "The Council of Wells", a roundtable of the brightest Harrison Wells’ from various Earths. 	When collectors of Native American artifacts are attacked by a meta named Mina Chayton who can bring inanimate objects to life, Barry turns to a surprising ally for help. Determined to crack the identity of The Thinker, Harry enlists Cisco’s help to summon the ultimate think tank; "The Council of Wells", a roundtable of the brightest Harrison Wells’ from various Earths. 	When collectors of Native American artifacts are attacked by a meta named Mina Chayton who can bring inanimate objects to life, Barry turns to a surprising ally for help. Determined to crack the identity of The Thinker, Harry enlists Cisco’s help to summon the ultimate think tank; "The Council of Wells", a roundtable of the brightest Harrison Wells’ from various Earths. 	When collectors of Native American artifacts are attacked by a meta named Mina Chayton who can bring inanimate objects to life, Barry turns to a surprising ally for help. Determined to crack the identity of The Thinker, Harry enlists Cisco’s help to summon the ultimate think tank; "The Council of Wells", a roundtable of the brightest Harrison Wells’ from various Earths. 	When collectors of Native American artifacts are attacked by a meta named Mina Chayton who can bring inanimate objects to life, Barry turns to a surprising ally for help. Determined to crack the identity of The Thinker, Harry enlists Cisco’s help to summon the ultimate think tank; "The Council of Wells", a roundtable of the brightest Harrison Wells’ from various Earths.
7 	 	David McWhirter 	Eric Wallace & Thomas Pound 	Eric Wallace & Thomas Pound 	November 21, 2017
Barry comes face to face with DeVoe. DeVoe's past is revealed through flashbacks. Meanwhile, Iris puts the final touches on the wedding, which is a week away. 	Barry comes face to face with DeVoe. DeVoe's past is revealed through flashbacks. Meanwhile, Iris puts the final touches on the wedding, which is a week away. 	Barry comes face to face with DeVoe. DeVoe's past is revealed through flashbacks. Meanwhile, Iris puts the final touches on the wedding, which is a week away. 	Barry comes face to face with DeVoe. DeVoe's past is revealed through flashbacks. Meanwhile, Iris puts the final touches on the wedding, which is a week away. 	Barry comes face to face with DeVoe. DeVoe's past is revealed through flashbacks. Meanwhile, Iris puts the final touches on the wedding, which is a week away. 	Barry comes face to face with DeVoe. DeVoe's past is revealed through flashbacks. Meanwhile, Iris puts the final touches on the wedding, which is a week away.
8 	 	Dermott Downs 	Andrew Kreisberg & Marc Guggenheim 	Todd Helbing 	November 28, 2017
Barry and Iris's wedding brings the gang together, but things go awry when villains from Earth-X attack the ceremony. All of the superheroes band together with help from their super friends like Citizen Cold, The Ray, Felicity Smoak, Iris West and Alex Danvers to take on their most formidable villains yet. Earth's mightiest heroes - Green Arrow, Supergirl, The Flash and White Canary - lead their teams into battle to save the world.	Barry and Iris's wedding brings the gang together, but things go awry when villains from Earth-X attack the ceremony. All of the superheroes band together with help from their super friends like Citizen Cold, The Ray, Felicity Smoak, Iris West and Alex Danvers to take on their most formidable villains yet. Earth's mightiest heroes - Green Arrow, Supergirl, The Flash and White Canary - lead their teams into battle to save the world.	Barry and Iris's wedding brings the gang together, but things go awry when villains from Earth-X attack the ceremony. All of the superheroes band together with help from their super friends like Citizen Cold, The Ray, Felicity Smoak, Iris West and Alex Danvers to take on their most formidable villains yet. Earth's mightiest heroes - Green Arrow, Supergirl, The Flash and White Canary - lead their teams into battle to save the world.	Barry and Iris's wedding brings the gang together, but things go awry when villains from Earth-X attack the ceremony. All of the superheroes band together with help from their super friends like Citizen Cold, The Ray, Felicity Smoak, Iris West and Alex Danvers to take on their most formidable villains yet. Earth's mightiest heroes - Green Arrow, Supergirl, The Flash and White Canary - lead their teams into battle to save the world.	Barry and Iris's wedding brings the gang together, but things go awry when villains from Earth-X attack the ceremony. All of the superheroes band together with help from their super friends like Citizen Cold, The Ray, Felicity Smoak, Iris West and Alex Danvers to take on their most formidable villains yet. Earth's mightiest heroes - Green Arrow, Supergirl, The Flash and White Canary - lead their teams into battle to save the world.	Barry and Iris's wedding brings the gang together, but things go awry when villains from Earth-X attack the ceremony. All of the superheroes band together with help from their super friends like Citizen Cold, The Ray, Felicity Smoak, Iris West and Alex Danvers to take on their most formidable villains yet. Earth's mightiest heroes - Green Arrow, Supergirl, The Flash and White Canary - lead their teams into battle to save the world.
9 	 	Stefan Pleszczynski 	Sam Chalsen & Judalina Neira 	Sam Chalsen & Judalina Neira 	December 5, 2017
Amunet kidnaps Caitlin and puts meta-dampener handcuffs on her to keep her from turning into Killer Frost. Amunet tells Caitlin she needs her to perform a tricky medical task and if Caitlin fails, Amunet will kill her. Meanwhile, The Thinker traps The Flash in a speedster-proof prison. With the clock ticking, The Team doesn't have the time or resources to track both Caitlin and Barry so Iris is forced to choose who to save. 	Amunet kidnaps Caitlin and puts meta-dampener handcuffs on her to keep her from turning into Killer Frost. Amunet tells Caitlin she needs her to perform a tricky medical task and if Caitlin fails, Amunet will kill her. Meanwhile, The Thinker traps The Flash in a speedster-proof prison. With the clock ticking, The Team doesn't have the time or resources to track both Caitlin and Barry so Iris is forced to choose who to save. 	Amunet kidnaps Caitlin and puts meta-dampener handcuffs on her to keep her from turning into Killer Frost. Amunet tells Caitlin she needs her to perform a tricky medical task and if Caitlin fails, Amunet will kill her. Meanwhile, The Thinker traps The Flash in a speedster-proof prison. With the clock ticking, The Team doesn't have the time or resources to track both Caitlin and Barry so Iris is forced to choose who to save. 	Amunet kidnaps Caitlin and puts meta-dampener handcuffs on her to keep her from turning into Killer Frost. Amunet tells Caitlin she needs her to perform a tricky medical task and if Caitlin fails, Amunet will kill her. Meanwhile, The Thinker traps The Flash in a speedster-proof prison. With the clock ticking, The Team doesn't have the time or resources to track both Caitlin and Barry so Iris is forced to choose who to save. 	Amunet kidnaps Caitlin and puts meta-dampener handcuffs on her to keep her from turning into Killer Frost. Amunet tells Caitlin she needs her to perform a tricky medical task and if Caitlin fails, Amunet will kill her. Meanwhile, The Thinker traps The Flash in a speedster-proof prison. With the clock ticking, The Team doesn't have the time or resources to track both Caitlin and Barry so Iris is forced to choose who to save. 	Amunet kidnaps Caitlin and puts meta-dampener handcuffs on her to keep her from turning into Killer Frost. Amunet tells Caitlin she needs her to perform a tricky medical task and if Caitlin fails, Amunet will kill her. Meanwhile, The Thinker traps The Flash in a speedster-proof prison. With the clock ticking, The Team doesn't have the time or resources to track both Caitlin and Barry so Iris is forced to choose who to save.
10 	 	Philip Chipera 	Lauren Certo & Kristen Kim 	Lauren Certo & Kristen Kim 	January 16, 2018
As Barry's trial for the murder of Clifford DeVoe begins, Iris and Joe must decide how far they are willing to go to keep Barry out of prison. 	As Barry's trial for the murder of Clifford DeVoe begins, Iris and Joe must decide how far they are willing to go to keep Barry out of prison. 	As Barry's trial for the murder of Clifford DeVoe begins, Iris and Joe must decide how far they are willing to go to keep Barry out of prison. 	As Barry's trial for the murder of Clifford DeVoe begins, Iris and Joe must decide how far they are willing to go to keep Barry out of prison. 	As Barry's trial for the murder of Clifford DeVoe begins, Iris and Joe must decide how far they are willing to go to keep Barry out of prison. 	As Barry's trial for the murder of Clifford DeVoe begins, Iris and Joe must decide how far they are willing to go to keep Barry out of prison.
11 	 	Alexandra La Roche 	Sterling Gates & Thomas Pound 	Sterling Gates & Thomas Pound 	January 23, 2018
When a familiar villain returns to terrorize Central City, Ralph must rise up to defend the innocent while Barry is detained by his trial. Meanwhile, Barry searches for the strength to keep his optimism alive in the face of his new circumstances. 	When a familiar villain returns to terrorize Central City, Ralph must rise up to defend the innocent while Barry is detained by his trial. Meanwhile, Barry searches for the strength to keep his optimism alive in the face of his new circumstances. 	When a familiar villain returns to terrorize Central City, Ralph must rise up to defend the innocent while Barry is detained by his trial. Meanwhile, Barry searches for the strength to keep his optimism alive in the face of his new circumstances. 	When a familiar villain returns to terrorize Central City, Ralph must rise up to defend the innocent while Barry is detained by his trial. Meanwhile, Barry searches for the strength to keep his optimism alive in the face of his new circumstances. 	When a familiar villain returns to terrorize Central City, Ralph must rise up to defend the innocent while Barry is detained by his trial. Meanwhile, Barry searches for the strength to keep his optimism alive in the face of his new circumstances. 	When a familiar villain returns to terrorize Central City, Ralph must rise up to defend the innocent while Barry is detained by his trial. Meanwhile, Barry searches for the strength to keep his optimism alive in the face of his new circumstances.
12 	 	Chris Peppe 	Sam Chalsen & Judalina Neira 	Sam Chalsen & Judalina Neira 	January 30, 2018
A meta who can shrink anything he touches battles Team Flash. Cisco and Ralph get caught in his crossfire and are shrunk to miniature versions of themselves. Cecile realizes her pregnancy has caused her to have temporary powers and discovers she can hear other people's thoughts, which unnerves Joe. Meanwhile, Barry meets someone with a mysterious connection to Henry Allen. 	A meta who can shrink anything he touches battles Team Flash. Cisco and Ralph get caught in his crossfire and are shrunk to miniature versions of themselves. Cecile realizes her pregnancy has caused her to have temporary powers and discovers she can hear other people's thoughts, which unnerves Joe. Meanwhile, Barry meets someone with a mysterious connection to Henry Allen. 	A meta who can shrink anything he touches battles Team Flash. Cisco and Ralph get caught in his crossfire and are shrunk to miniature versions of themselves. Cecile realizes her pregnancy has caused her to have temporary powers and discovers she can hear other people's thoughts, which unnerves Joe. Meanwhile, Barry meets someone with a mysterious connection to Henry Allen. 	A meta who can shrink anything he touches battles Team Flash. Cisco and Ralph get caught in his crossfire and are shrunk to miniature versions of themselves. Cecile realizes her pregnancy has caused her to have temporary powers and discovers she can hear other people's thoughts, which unnerves Joe. Meanwhile, Barry meets someone with a mysterious connection to Henry Allen. 	A meta who can shrink anything he touches battles Team Flash. Cisco and Ralph get caught in his crossfire and are shrunk to miniature versions of themselves. Cecile realizes her pregnancy has caused her to have temporary powers and discovers she can hear other people's thoughts, which unnerves Joe. Meanwhile, Barry meets someone with a mysterious connection to Henry Allen. 	A meta who can shrink anything he touches battles Team Flash. Cisco and Ralph get caught in his crossfire and are shrunk to miniature versions of themselves. Cecile realizes her pregnancy has caused her to have temporary powers and discovers she can hear other people's thoughts, which unnerves Joe. Meanwhile, Barry meets someone with a mysterious connection to Henry Allen.
13 	 	Tara Nicole Weyr 	Jonathan Butler & Gabriel Garza 	Jonathan Butler & Gabriel Garza 	February 6, 2018
After hearing that Amunet has struck a deal to buy all of the metahumans in Iron Heights, Barry must decide if he should expose his powers in order to save his cellmates. After a visit from an old friend, Ralph is reminded of his shady past and wonders if he's really a changed man. 	After hearing that Amunet has struck a deal to buy all of the metahumans in Iron Heights, Barry must decide if he should expose his powers in order to save his cellmates. After a visit from an old friend, Ralph is reminded of his shady past and wonders if he's really a changed man. 	After hearing that Amunet has struck a deal to buy all of the metahumans in Iron Heights, Barry must decide if he should expose his powers in order to save his cellmates. After a visit from an old friend, Ralph is reminded of his shady past and wonders if he's really a changed man. 	After hearing that Amunet has struck a deal to buy all of the metahumans in Iron Heights, Barry must decide if he should expose his powers in order to save his cellmates. After a visit from an old friend, Ralph is reminded of his shady past and wonders if he's really a changed man. 	After hearing that Amunet has struck a deal to buy all of the metahumans in Iron Heights, Barry must decide if he should expose his powers in order to save his cellmates. After a visit from an old friend, Ralph is reminded of his shady past and wonders if he's really a changed man. 	After hearing that Amunet has struck a deal to buy all of the metahumans in Iron Heights, Barry must decide if he should expose his powers in order to save his cellmates. After a visit from an old friend, Ralph is reminded of his shady past and wonders if he's really a changed man.
14 	 	Ralph Hemecker 	Mike Alber & Gabe Snyder 	Mike Alber & Gabe Snyder 	February 27, 2018
Barry meets a powerful woman whose abilities could help him in his battle with DeVoe. Meanwhile, after learning that DeVoe is targeting everyone who was on the bus, Ralph decides he doesn't want to be a hero anymore, his only concern is staying alive. Harry offers to help Joe. 	Barry meets a powerful woman whose abilities could help him in his battle with DeVoe. Meanwhile, after learning that DeVoe is targeting everyone who was on the bus, Ralph decides he doesn't want to be a hero anymore, his only concern is staying alive. Harry offers to help Joe. 	Barry meets a powerful woman whose abilities could help him in his battle with DeVoe. Meanwhile, after learning that DeVoe is targeting everyone who was on the bus, Ralph decides he doesn't want to be a hero anymore, his only concern is staying alive. Harry offers to help Joe. 	Barry meets a powerful woman whose abilities could help him in his battle with DeVoe. Meanwhile, after learning that DeVoe is targeting everyone who was on the bus, Ralph decides he doesn't want to be a hero anymore, his only concern is staying alive. Harry offers to help Joe. 	Barry meets a powerful woman whose abilities could help him in his battle with DeVoe. Meanwhile, after learning that DeVoe is targeting everyone who was on the bus, Ralph decides he doesn't want to be a hero anymore, his only concern is staying alive. Harry offers to help Joe. 	Barry meets a powerful woman whose abilities could help him in his battle with DeVoe. Meanwhile, after learning that DeVoe is targeting everyone who was on the bus, Ralph decides he doesn't want to be a hero anymore, his only concern is staying alive. Harry offers to help Joe.
15 	 	Gregory Smith 	Todd Helbing & Sterling Gates 	Todd Helbing & Sterling Gates 	March 6, 2018
When a nuclear bomb detonates in downtown Central City, Barry, Jesse Quick and Jay Garrick slow down time by entering Flashtime. As everyone in the city is frozen, the three speedsters push themselves to the breaking point to save the city and everyone in it. 	When a nuclear bomb detonates in downtown Central City, Barry, Jesse Quick and Jay Garrick slow down time by entering Flashtime. As everyone in the city is frozen, the three speedsters push themselves to the breaking point to save the city and everyone in it. 	When a nuclear bomb detonates in downtown Central City, Barry, Jesse Quick and Jay Garrick slow down time by entering Flashtime. As everyone in the city is frozen, the three speedsters push themselves to the breaking point to save the city and everyone in it. 	When a nuclear bomb detonates in downtown Central City, Barry, Jesse Quick and Jay Garrick slow down time by entering Flashtime. As everyone in the city is frozen, the three speedsters push themselves to the breaking point to save the city and everyone in it. 	When a nuclear bomb detonates in downtown Central City, Barry, Jesse Quick and Jay Garrick slow down time by entering Flashtime. As everyone in the city is frozen, the three speedsters push themselves to the breaking point to save the city and everyone in it. 	When a nuclear bomb detonates in downtown Central City, Barry, Jesse Quick and Jay Garrick slow down time by entering Flashtime. As everyone in the city is frozen, the three speedsters push themselves to the breaking point to save the city and everyone in it.
16 	 	Harry Jierjian 	Eric Wallace 	Eric Wallace 	March 13, 2018
Team Flash confronts a new bus meta, Matthew AKA Melting Point, with the ability to swap people's DNA. During a battle with Team Flash, Matthew transfers Barry's super speed to Iris. Now, with a new threat unleashed on Central City, Barry must act as the team leader while Iris takes on the mantle of superhero speedster in order to defeat their new foe. 	Team Flash confronts a new bus meta, Matthew AKA Melting Point, with the ability to swap people's DNA. During a battle with Team Flash, Matthew transfers Barry's super speed to Iris. Now, with a new threat unleashed on Central City, Barry must act as the team leader while Iris takes on the mantle of superhero speedster in order to defeat their new foe. 	Team Flash confronts a new bus meta, Matthew AKA Melting Point, with the ability to swap people's DNA. During a battle with Team Flash, Matthew transfers Barry's super speed to Iris. Now, with a new threat unleashed on Central City, Barry must act as the team leader while Iris takes on the mantle of superhero speedster in order to defeat their new foe. 	Team Flash confronts a new bus meta, Matthew AKA Melting Point, with the ability to swap people's DNA. During a battle with Team Flash, Matthew transfers Barry's super speed to Iris. Now, with a new threat unleashed on Central City, Barry must act as the team leader while Iris takes on the mantle of superhero speedster in order to defeat their new foe. 	Team Flash confronts a new bus meta, Matthew AKA Melting Point, with the ability to swap people's DNA. During a battle with Team Flash, Matthew transfers Barry's super speed to Iris. Now, with a new threat unleashed on Central City, Barry must act as the team leader while Iris takes on the mantle of superhero speedster in order to defeat their new foe. 	Team Flash confronts a new bus meta, Matthew AKA Melting Point, with the ability to swap people's DNA. During a battle with Team Flash, Matthew transfers Barry's super speed to Iris. Now, with a new threat unleashed on Central City, Barry must act as the team leader while Iris takes on the mantle of superhero speedster in order to defeat their new foe.
17 	 	Kevin Smith 	Lauren Certo & Kristen Kim 	Lauren Certo & Kristen Kim 	April 10, 2018
Barry and Ralph take different approaches to finding the remaining bus metas before DeVoe gets to them. However, Ralph's cavalier attitude frustrates Barry and the two clash over what it means to be a hero. Meanwhile, Breacher returns to ask Cisco for a favor. 	Barry and Ralph take different approaches to finding the remaining bus metas before DeVoe gets to them. However, Ralph's cavalier attitude frustrates Barry and the two clash over what it means to be a hero. Meanwhile, Breacher returns to ask Cisco for a favor. 	Barry and Ralph take different approaches to finding the remaining bus metas before DeVoe gets to them. However, Ralph's cavalier attitude frustrates Barry and the two clash over what it means to be a hero. Meanwhile, Breacher returns to ask Cisco for a favor. 	Barry and Ralph take different approaches to finding the remaining bus metas before DeVoe gets to them. However, Ralph's cavalier attitude frustrates Barry and the two clash over what it means to be a hero. Meanwhile, Breacher returns to ask Cisco for a favor. 	Barry and Ralph take different approaches to finding the remaining bus metas before DeVoe gets to them. However, Ralph's cavalier attitude frustrates Barry and the two clash over what it means to be a hero. Meanwhile, Breacher returns to ask Cisco for a favor. 	Barry and Ralph take different approaches to finding the remaining bus metas before DeVoe gets to them. However, Ralph's cavalier attitude frustrates Barry and the two clash over what it means to be a hero. Meanwhile, Breacher returns to ask Cisco for a favor.
18 	 	Hanelle Culpepper 	Jonathan Butler & Gabriel Garza 	Jonathan Butler & Gabriel Garza 	April 17, 2018
When Barry and Team Flash find a way to enter the Thinker's lair, Ralph considers crossing a dangerous line to defeat DeVoe. Meanwhile, Joe is concerned by Harry’s recent behavior. 	When Barry and Team Flash find a way to enter the Thinker's lair, Ralph considers crossing a dangerous line to defeat DeVoe. Meanwhile, Joe is concerned by Harry’s recent behavior. 	When Barry and Team Flash find a way to enter the Thinker's lair, Ralph considers crossing a dangerous line to defeat DeVoe. Meanwhile, Joe is concerned by Harry’s recent behavior. 	When Barry and Team Flash find a way to enter the Thinker's lair, Ralph considers crossing a dangerous line to defeat DeVoe. Meanwhile, Joe is concerned by Harry’s recent behavior. 	When Barry and Team Flash find a way to enter the Thinker's lair, Ralph considers crossing a dangerous line to defeat DeVoe. Meanwhile, Joe is concerned by Harry’s recent behavior. 	When Barry and Team Flash find a way to enter the Thinker's lair, Ralph considers crossing a dangerous line to defeat DeVoe. Meanwhile, Joe is concerned by Harry’s recent behavior.
19 	 	Rachel Talalay 	Joshua V. Gilbert & Jeff Hersh 	Joshua V. Gilbert & Jeff Hersh 	April 24, 2018
When Barry needs help transporting a dangerous meta, he calls on a new friend for help - Citizen Cold; Cisco becomes suspicious of Harry. 	When Barry needs help transporting a dangerous meta, he calls on a new friend for help - Citizen Cold; Cisco becomes suspicious of Harry. 	When Barry needs help transporting a dangerous meta, he calls on a new friend for help - Citizen Cold; Cisco becomes suspicious of Harry. 	When Barry needs help transporting a dangerous meta, he calls on a new friend for help - Citizen Cold; Cisco becomes suspicious of Harry. 	When Barry needs help transporting a dangerous meta, he calls on a new friend for help - Citizen Cold; Cisco becomes suspicious of Harry. 	When Barry needs help transporting a dangerous meta, he calls on a new friend for help - Citizen Cold; Cisco becomes suspicious of Harry.
20 	 	Rob J. Greenlea 	Sterling Gates & Thomas Pound 	Sterling Gates & Thomas Pound 	May 1, 2018
Barry and Team Flash team up with Gypsy to try to thwart the Thinker's plan. Meanwhile, Cisco and Gypsy have a heart to heart talk about their relationship. 	Barry and Team Flash team up with Gypsy to try to thwart the Thinker's plan. Meanwhile, Cisco and Gypsy have a heart to heart talk about their relationship. 	Barry and Team Flash team up with Gypsy to try to thwart the Thinker's plan. Meanwhile, Cisco and Gypsy have a heart to heart talk about their relationship. 	Barry and Team Flash team up with Gypsy to try to thwart the Thinker's plan. Meanwhile, Cisco and Gypsy have a heart to heart talk about their relationship. 	Barry and Team Flash team up with Gypsy to try to thwart the Thinker's plan. Meanwhile, Cisco and Gypsy have a heart to heart talk about their relationship. 	Barry and Team Flash team up with Gypsy to try to thwart the Thinker's plan. Meanwhile, Cisco and Gypsy have a heart to heart talk about their relationship.
21 	 	Kevin Mock 	Judalina Neira & Lauren Certo 	Judalina Neira & Lauren Certo 	May 8, 2018
With DeVoe's Enlightenment device nearly complete, in order to disable it the Flash and his team must put their faith in an unlikely ally - Amunet Black. Meanwhile, Harry hits an all-time low when the "Council of Wells" kicks him out but then Cisco introduces him to the "Council of Harrisons". 	With DeVoe's Enlightenment device nearly complete, in order to disable it the Flash and his team must put their faith in an unlikely ally - Amunet Black. Meanwhile, Harry hits an all-time low when the "Council of Wells" kicks him out but then Cisco introduces him to the "Council of Harrisons". 	With DeVoe's Enlightenment device nearly complete, in order to disable it the Flash and his team must put their faith in an unlikely ally - Amunet Black. Meanwhile, Harry hits an all-time low when the "Council of Wells" kicks him out but then Cisco introduces him to the "Council of Harrisons". 	With DeVoe's Enlightenment device nearly complete, in order to disable it the Flash and his team must put their faith in an unlikely ally - Amunet Black. Meanwhile, Harry hits an all-time low when the "Council of Wells" kicks him out but then Cisco introduces him to the "Council of Harrisons". 	With DeVoe's Enlightenment device nearly complete, in order to disable it the Flash and his team must put their faith in an unlikely ally - Amunet Black. Meanwhile, Harry hits an all-time low when the "Council of Wells" kicks him out but then Cisco introduces him to the "Council of Harrisons". 	With DeVoe's Enlightenment device nearly complete, in order to disable it the Flash and his team must put their faith in an unlikely ally - Amunet Black. Meanwhile, Harry hits an all-time low when the "Council of Wells" kicks him out but then Cisco introduces him to the "Council of Harrisons".
22 	 	Viet Nguyen 	Sam Chalsen & Kristen Kim 	Sam Chalsen & Kristen Kim 	May 15, 2018
When DeVoe assaults an A.R.G.U.S. facility to complete his Enlightenment Machine, Barry realizes the only way he can stop him is if he allows Cisco and Caitlin to accompany him into the facility. Still shaken by Ralph's death, Barry isn't sure he wants to risk any more of his friends' lives and considers taking on DeVoe solo. 	When DeVoe assaults an A.R.G.U.S. facility to complete his Enlightenment Machine, Barry realizes the only way he can stop him is if he allows Cisco and Caitlin to accompany him into the facility. Still shaken by Ralph's death, Barry isn't sure he wants to risk any more of his friends' lives and considers taking on DeVoe solo. 	When DeVoe assaults an A.R.G.U.S. facility to complete his Enlightenment Machine, Barry realizes the only way he can stop him is if he allows Cisco and Caitlin to accompany him into the facility. Still shaken by Ralph's death, Barry isn't sure he wants to risk any more of his friends' lives and considers taking on DeVoe solo. 	When DeVoe assaults an A.R.G.U.S. facility to complete his Enlightenment Machine, Barry realizes the only way he can stop him is if he allows Cisco and Caitlin to accompany him into the facility. Still shaken by Ralph's death, Barry isn't sure he wants to risk any more of his friends' lives and considers taking on DeVoe solo. 	When DeVoe assaults an A.R.G.U.S. facility to complete his Enlightenment Machine, Barry realizes the only way he can stop him is if he allows Cisco and Caitlin to accompany him into the facility. Still shaken by Ralph's death, Barry isn't sure he wants to risk any more of his friends' lives and considers taking on DeVoe solo. 	When DeVoe assaults an A.R.G.U.S. facility to complete his Enlightenment Machine, Barry realizes the only way he can stop him is if he allows Cisco and Caitlin to accompany him into the facility. Still shaken by Ralph's death, Barry isn't sure he wants to risk any more of his friends' lives and considers taking on DeVoe solo.
23 	 	David McWhirter 	Todd Helbing & Eric Wallace 	Todd Helbing & Eric Wallace 	May 22, 2018
Team Flash gets help from a surprising ally in their battle against DeVoe. 	Team Flash gets help from a surprising ally in their battle against DeVoe. 	Team Flash gets help from a surprising ally in their battle against DeVoe. 	Team Flash gets help from a surprising ally in their battle against DeVoe. 	Team Flash gets help from a surprising ally in their battle against DeVoe. 	Team Flash gets help from a surprising ally in their battle against DeVoe.
== Trivia ==
*This was the first season of ​​​:
**Where , , , , , , , and didn't reprise their respective roles.
***However, Miller portrayed Leonard Snart's Earth-X doppelgänger and Shipp reprised his role as Jay Garrick/The Flash in .
**Where Grodd was not featured since his prievious appearance in .
**Where King Shark was not featured since his previous appearance in .
***Though King Shark did make a cameo in episode, .
**To not feature  in every episode.
**To have a main antagonist that wasn't a speedster.
**To not feature time travel.
*This was the only season of The Flash to feature Neil Sandilands as a series regular.
*This is the last season of The Flash to have 23 episodes; future seasons would have fewer episodes. In addition to feature Andrew Kreisberg as co-showrunner until he was fired in late 2017 admist the sexual harassment allegations with Greg Berlanti stepping in to help out Todd Helbing finish the rest of the fourth season.
==Gallery==
===Title cards===
The Flash seasons 4-5 title card.png
Crisis on Earth-X title card.png|Variant title card from 
We Are The Flash title card.png|Variant title card for the season finale 
===Promotional images===
The Flash season 4 poster - Reborn. Recharged.png|"Reborn. Recharged."
The Flash season 4 poster - Catch the Vibe.png|"Catch the Vibe"
The Flash season 4 poster - Frost Warning!.png|"Frost Warning!"
The Flash season 4 poster - Speeding Toward a Showdown.png|"Speeding Toward a Showdown"
The Flash season 4 poster - Let the Mind Games Begin.png|"Let the Mind Games Begin"
The Flash season 4 poster - Save the Date.png|"Save the Date"
Iris West-Allen costumed first look.png|First look at Iris West's costume.
The Flash season 4 poster - Outmatched? Think Again!.png|"Outmatched? Think Again!"
The Flash season 4 poster - It Takes a Villain....png|"It Takes a Villain..."
The Flash season 4 poster - Team Up. Speed Up..png|"Team Up. Speed Up."
The Flash season 4 poster - A Mind-Blowing Finale.png|"A Mind-Blowing Finale"
===Videos===
The Flash Comic-Con® 2017 Video The CW
DC TV "Save the Day" Promo (HD) The Flash, Arrow, Supergirl, DC's Legends of Tomorrow
The Flash Season 4 Producer's Preview (HD)
The Flash The Flash Reborn Trailer The CW
The Flash Inside The Flash Season 4 Behind The Scenes The CW
The Flash The Flash Official Season 4 Extended Trailer The CW
The Flash Therapy Trailer The CW
DCTV Crisis on Earth-X Crossover Teaser - The Flash, Arrow, Supergirl, DC's Legends of Tomorrow (HD)
Crisis On Earth-X Sizzle The CW
Crisis on Earth-X Weapon Trailer The CW
The Flash Catch Up The CW
The Flash Get Up And Go Extended Trailer The CW
==References==
es:Temporada 4 (The Flash)
fr:Saison 4 (The Flash)
pl:Sezon 4 (Flash)
pt-br:4ª Temporada (Flash)