Keiichi Hasegawa

is a Japanese screenwriter who served as secondary writer of Kamen Rider W, Kamen Rider Fourze, Kamen Rider Drive, Kamen Rider Ghost and Kamen Rider Saber. He and Hiroki Uchida served as co-headwriters of Kamen Rider Gotchard. 
He is more known for his work on the Ultra Series, having written for every Ultraman series produced from through (with the exception of ), he has written more material for the franchise than any other writer.
He also played a drunken man in Kamen Rider W Returns: Kamen Rider Accel, and a Humagear in Episode 47 of Kamen Rider Saber.
==Writing credits==
===Television===
*Kamen Rider W (2009-2010)
** Episode 11: The Revenge V/Infected Car
** Episode 12: The Revenge V/Grudge Beast
**Episode 13: The Q on the Radio/Targeted Princess
**Episode 14: The Q on the Radio/Live Catastrophe
**Episode 17: Farewell N/Memory Kids
**Episode 18: Farewell N/The Friend with the Wind
**Episode 21: The T Returns/A Melody Not Intended for Women
**Episode 22: The T Returns/The Man Who Cannot Die
**Episode 25: The P's Game/The Doll Has Sticky Fingers
**Episode 26: The P's Game/Akiko on the Run
**Episode 29: The Nightmarish H/The Melancholy of the Sleeping Princess
**Episode 30: The Nightmarish H/Who Is the Prince?
**Episode 35: Beyond the R/The Rain Called Monster Approaches
**Episode 36: Beyond the R/Surpass Them All
**Episode 37: Visitor X/The Bridge of Promises
**Episode 38: Visitor X/In the Name of the Museum
**Episode 41: The J Labyrinth/The Psychotic Villainess
**Episode 42: The J Labyrinth/The Diamond Is Hurt
** Episode 43: The O Chain/The Aged Detective
**Episode 44: The O Chain/Shroud's Confession
*Kamen Rider Fourze (2012) 
**Episode 23: Swan Alliance
**Episode 24: Hero's Desire
** Episode 29: Junior Silence
**Episode 30: Senior, Useless
**Episode 35: Monster's Broadcast
**Episode 36: Serious Legend Song
**Episode 39: Campus Decree
**Episode 40: Principle or Pathos
*Kamen Rider Drive (2014-2015)
**Episode 7: How Was That Decisive Moment Captured?
**Episode 8: What is the Secret That Dwells in the Heart?
**Episode 14: Who Is the Black Shadow Chasing Her?
**Episode 15: When Will These Feelings Reach You?
**Episode 18: Why is Lt. Otta Following That Guy?
** Episode 19: What Can Judge the Police?
**Episode 27: What's Go Shijima's Reason to Fight?
**Episode 28: Why Were the Families Targeted?
**Episode 31: Why Did the Important Memories Disappear?
**Episode 32: What is Waiting At the End of Evolution?
**Episode 35: Why Did the Siege Happen?
**Episode 36: Where Will the Bullet Guide Justice?
**Episode 41: How is the Golden Drive Born?
**Episode 42: Where is the Truth About the Goddess?
*Kamen Rider Ghost (2016)
** Episode 17: Gorgeous! The Fantastic Queen!
**Episode 18: Reverse! Mysterious Science!
**Episode 21: Amazing! The Gamma's World!
**Episode 22: Conspiracy! Adel's Trap!
**Episode 25: Disaster! The Red Sky!
**Episode 26: Conflict! The Terms of Resolution! 
**Episode 31: Bizarre! Power of the Gammaizers!
**Episode 32: Reminiscence! Secret of the Mind! 
**Episode 33: Miracle! Infinite Thought! 
** Episode 36: Furious! Idol's Declaration! 
**Episode 37: Learn! All the Ways!
**Episode 41: Upheaval! The Magistrate's Decision!
** Episode 42: Astonishing! Hermit's Truth! 
** Episode 45: Horrible! Disappearing World!
**Episode 46: Duel! Words from the Swordsman!
*Kamen Rider Saber (2020-2021)
**Episode 7: Chapter 7: The Sword of the King, Lies in Avalon.
**Episode 8: Chapter 8: The One That Is Sealed Is, Arthur.
**Episode 11: Chapter 11: Disturbed Thunder, Spreading Dark Clouds.
**Episode 12: Chapter 12: The Promise, in that Place.
**Episode 15: Chapter 15: Beyond The Resolution, and Beyond.
**Episode 16: Chapter 16: Saving the World, A Ray of Light.
**Episode 21: Chapter 21: Shine the Best, Full Color.
**Episode 22: Chapter 22: Nevertheless, I Want to Save People.
**Episode 27: Chapter 27: Sorrow, Turn It Into a Smile.
**Episode 28: Chapter 28: Writing the Past, Drawing the Future.
**Episode 29: Chapter 29: At That Moment, the Swordsman Made His Move.
**Episode 34: Chapter 34: Wake Up, Immortal Swordsman.
**Episode 35: Chapter 35: And I, Become a God.
**Episode 40: Chapter 40: Shining Friendship, the Three Swordsmen.
**Episode 41: Chapter 41: For 2,000 Years, a Wish Spelled Out.
**Episode 44: Chapter 44: Open, The Last Page.
**Episode 45: Chapter 45: Ten Swordsmen, Betting the World.
**Episode 46: Chapter 46: Goodbye, My Hero.
**Episode 47: Final Chapter: The End of the World, the Story that is Born.
*Kamen Rider Gotchard (2023-2024) 
**Episode 1: Gotcha! Hopper1! (with Hiroki Uchida)
**Episode 2: Pursuit, Alchemy, Skebows! (with Hiroki Uchida)
**Episode 3: Bushido, Found.
**Episode 4: Antrooper Labyrinth
**Episode 5: Burn! Fight! Wrestler G!
**Episode 6: Super A-Class ☆ Twisted Star
**Episode 9: Dash to Kyoto! School Trip!‎
**Episode 10: Kyoto on Fire! ~ Sad Love: Chemy Thunder Incident ~
**Episode 11: Catch! A Spy!? Rider Disqualified!?
**Episode 12: Runaway Liner! Dark Rider!
**Episode 13: Take It Back! Friendship × Forever!
**Episode 14: Chomping Rex! Dangerous X
**Episode 15: Seize the Happy! Shine Bright Gotchalibur!
**Episode 20: Smiling Angel, Ridiculous Joke
**Episode 21: Mad Warrior! Valvarad the Black Flame!
**Episode 26: Thwart Malice, Jet Black Wind
**Episode 27: Gotcha! Crosshopper!
**Episode 30: A Rival Arrives!? Gotcha and Juliet
**Episode 31: Two People in the Dark, Trusting Each Other.
**Episode 44: When Deep Memories Open Up
**Episode 45: A Fateful Encounter, a Junction of Love and Hate!
===Movies===
*Kamen Rider W Returns: Kamen Rider Accel (2011)
*Drive Saga: Kamen Rider Mach (2016)
*Kamen Rider Gotchard: The Future Daybreak (2024)
===Special===
*Kamen Rider Fourze the Net Edition: Everyone, Class is Here! (2012)
*Kamen Rider Drive: Secret Mission (2014)
**Type ZERO Episode 0: Countdown to Global Freeze
*Type TV-KUN: Hunter & Monster! Chase the Mystery of the Super Thief! (2014)
*We Are Class 3G (2024)
*Kamen Rider Gotchard Ver.: Romeo and Juliet Complete Edition (2024)
==Trivia==
*Hasegawa remarked that various tokusatsu franchises most notably Kamen Rider and Ultraman franchises since Heisei era were largely influenced by the Heisei Gamera Trilogy, which was based on a scrapped Gamera script that later became the basis for Ryuta Tasaki's Gamera the Brave and Digimon Tamers and Ultraman Tiga, where various influential practical knowledges and tokusatsu techniques were invented during the production of the trilogy.ASCII MEDIA WORKS, 2014, Heisei Gamera Perfection, p.75, p.80, p.87, p.159, Kadokawa Shoten
==References==
==External links==
*Keiichi Hasegawa at Wikipedia
* at the 
Category:Writers
Category:Actors
Category:Kamen Rider W
Category:Kamen Rider Fourze
Category:Kamen Rider Drive
Category:Kamen Rider Ghost
Category:Kamen Rider Saber
Category:Kamen Rider Gotchard
Category:Head Writers