Grey 's Anatomy ( season 4 ) - wikipedia Grey 's Anatomy ( season 4 ) Grey 's Anatomy ( season 4 ) DVD cover art for the fourth season of Grey 's Anatomy Starring Ellen Pompeo Sandra Oh Katherine Heigl Justin Chambers T.R. Knight Chandra Wilson James Pickens, Jr. Sara Ramirez Eric Dane Chyler Leigh Brooke Smith Patrick Dempsey Country of origin United States No. of episodes 17 Release Original network ABC Original release September 27, 2007 ( 2007 - 09 - 27 ) -- May 22, 2008 ( 2008 - 05 - 22 ) Season chronology ← Previous Season 3 Next → Season 5 List of Grey 's Anatomy episodes The fourth season of the American television medical drama Grey 's Anatomy, commenced airing in the United States on September 27, 2007 and concluded on May 22, 2008. The season continues the story of a group of surgeons and their mentors in the fictional Seattle Grace Hospital, describing their professional lives and the way they affect the personal background of each character. Season four had twelve series regulars with ten of them returning from the previous season, out of which eight are part of the original cast from the first season. The season aired in the Thursday night timeslot at 9 : 00 EST. In addition to the regular seventeen episodes, a clip - show narrated by the editors of People recapped previous events of the show and made the transition from Grey 's Anatomy to Private Practice, a spin - off focusing on Dr. Addison Montgomery and aired on September 19, 2007, before the season premiere. The season was officially released on DVD as a five - disc boxset under the title of Grey 's Anatomy : Season Four -- Expanded on September 9, 2008 by Buena Vista Home Entertainment. For the first time in the show 's history, many cast changes occur, seeing the first departure of two main cast members. Despite garnering several awards and nominations for the cast members and the production team, the season received a mixed response from critics and fans. Show creator Shonda Rhimes heavily contributed to the production of the season, writing five out of the seventeen episodes. The highest - rated episode was the season premiere, which was watched by 20.93 million viewers. The season was interrupted by the 2007 -- 2008 Writers Guild of America strike, which resulted in the production of only seventeen episodes, instead of twenty - three originally planned. Contents 1 Production 2 Cast 2.1 Main cast 2.2 Recurring cast 2.3 Guest stars 3 Reception 4 Episodes 5 DVD Release 6 References Production This is the first season to be produced by ABC Studios under its current name, after the transition from Touchstone Television in May 2007. It was also produced by ShondaLand Production Company, and The Mark Gordon Company, whereas Buena Vista International, Inc. distributed it. The executive producers were creator and show runner Shonda Rhimes, Betsy Beers, Mark Gordon, Krista Vernoff, Rob Corn, Mark Wilding, Joan Rater, and James D. Parriott, all part of the production team since the series ' inception. The regular directors were Rob Corn and Jessica Yu. Producer Shonda Rhimes wrote five of the seventeen episodes, two of which were along with fellow producer Krista Vernoff. Unlike the other seasons, except from the first one, which aired mid-season, the fourth season of Grey 's Anatomy had a reduced number of episodes, due to the 2007 -- 2008 Writers Guild of America strike, which caused the production to cease from February to April, leaving the show with no writing staff during that time. Since the show had only produced ten episodes before the winter - holiday hiatus, and aired another one after the break ended, the show decided to complete the season with six new episodes, and returned on April 24, 2008. Only seventeen episodes were produced out of the twenty - three originally conceived for the season. After Kate Walsh 's transition the Grey 's Anatomy spin - off, Private Practice, her character left the show after a two - year run. On June 7, 2007, it was announced that Isaiah Washington 's contract had not been renewed. Former Reunion star, Chyler Leigh, guest starred in the final two episodes of season three as Lexie Grey, a new intern and Meredith Grey 's younger half - sister. On June 11, 2007, it was announced that Leigh would become a series regular, instead of a 13 episode story arc as previously planned. The character Dr. Erica Hahn, portrayed by Brooke Smith joined the main cast, reprising her antagonizing role in the season 's fifth episode. She replaces Preston Burke as head of Cardiothoracics. Upon her return, she makes Sandra Oh 's character, Cristina Yang work harder for her success in Cardiothoracics and initially served as a new love interest for Eric Dane 's Mark Sloan. Even though a new male character was originally thought to be introduced as a rival for Dr. Derek Shepherd, the change did n't occur. Former Dawson 's Creek star Joshua Jackson was scheduled to make his return to television in a multi-episode arc as a doctor with his first appearance in the season 's eleventh episode. Jackson 's appearance was cancelled due to the 2007 -- 2008 Writers Guild of America strike, and the storyline of the character he was supposed to play has never been aired on the show. Cast Main articles : List of Grey 's Anatomy cast members and List of Grey 's Anatomy characters Main cast Ellen Pompeo as Dr. Meredith Grey Sandra Oh as Dr. Cristina Yang Katherine Heigl as Dr. Izzie Stevens Justin Chambers as Dr. Alex Karev T.R. Knight as Dr. George O'Malley Chandra Wilson as Dr. Miranda Bailey James Pickens, Jr. as Dr. Richard Webber Sara Ramirez as Dr. Callie Torres Eric Dane as Dr. Mark Sloan Chyler Leigh as Dr. Lexie Grey Brooke Smith as Dr. Erica Hahn ( From Episode 5 ) Patrick Dempsey as Dr. Derek Shepherd Recurring cast Lauren Stamile as Nurse Rose Sarah Utterback as Nurse Olivia Harper Diahann Carroll as Jane Burke Jack Axelrod as Charlie `` Really Old Guy '' Yost Edward Herrmann as Norman Shales Kali Rocha as Sydney Heron Elizabeth Reaser as Rebecca `` Ava '' Pope Loretta Devine as Adele Webber Anjul Nigam as Dr. Raj Sen Jeff Perry as Thatcher Grey Debra Monk as Louise O'Malley Mark Saul as Dr. Steve Mostow Amy Madigan as Dr. Katharine Wyatt Cress Williams as Tucker Jones Guest stars Kate Walsh as Dr. Addison Montgomery Mark Pellegrino as Chris Caroline Aaron as Connie Michael McGrady as Stanley Singer Miriam Flynn as Gretchen Bitzer Amy Hill as Joanne David Clennon as Jack Shandley Kurt Fuller as Jerry Seth Green as Nick Hanscom Gale Harold as Paramedic Shane John Billingsley as Jacob Nolston Alison LaPlaca as Mrs. Nolston Kimberly Huie as Mary Daltrey Theo Rossi as Stan Giamatti Cheech Marin as Otis Sharon Paul Dooley as Dr. Walter Tapley John Cothran as Ken Monroe Kathryn Meisle as Liz Monroe Jurnee Smollett as Beth Monroe Jana Kramer as Lola James Immekus as Andrew Langston Sterling Knight as Kip Washington was fired before the inception of the season, due to an alleged homophobic insult regarding Knight. The fourth season had twelve roles receiving star billing, with ten of them returning from the previous season, eight of whom are part of the original cast from the first one. All the actors who are billed as series regulars portray physicians from the surgical wing of the fictional Seattle Grace Hospital. The majority of the show 's episodes are narrated by Ellen Pompeo, who portrayed protagonist Dr. Meredith Grey, a surgical resident whose storylines are the series ' focal points. Sandra Oh acted as Meredith 's best friend, highly competitive resident Dr. Cristina Yang. Fellow resident Dr. Isobel `` Izzie '' Stevens was portrayed by Katherine Heigl, while Dr. Alexander `` Alex '' Karev was played by Justin Chambers. T.R. Knight acted as insecure resident with self - confidence issues, Dr. George O'Malley, whereas Chandra Wilson portrayed Chief Resident and general surgeon Dr. Miranda Bailey, former mentor of the five residents during their internship. James Pickens, Jr. portrayed attending physician and general surgeon Dr. Richard Webber, who continues his position as Chief of Surgery, despite his former wishes of retirement. Orthopedic surgeon and fifth - year resident Dr. Calliope `` Callie '' Torres, who was portrayed by Sara Ramirez, has to face her husband 's unfaithfulness and her unexpected bisexuality. Attending plastic surgeon, Dr. Mark Sloan was portrayed by Eric Dane, who is constantly seeking reconciliation with former best friend, attending physician and Chief of Neurosurgery Dr. Derek Shepherd ( Patrick Dempsey ), whose lasting relationship with Meredith Grey faces difficulties. Former Reunion star Chyler Leigh was promoted to series regular status, after short appearances in the final two episodes of the third season, portraying Meredith 's half - sister Lexie Grey, who opts for a surgical internship at Seattle Grace Hospital against Massachusetts General Hospital, after her mother 's sudden death. Silence of the Lambs star, Brooke Smith was upgraded to series regular status after multiple guest appearances in the second and third seasons. An antagonizing character at first, she replaces Preston Burke as the Chief of Cardiothoracic Surgery, constantly displaying disrespect for Cristina 's previous relationship with him. Numerous supporting characters have been given recurring appearances in the progressive storyline, including former Gilmore Girls actor Edward Herrmann who appeared in three episodes. Seth Green of Buffy the Vampire Slayer guest starred in two episodes, whereas Lauren Stamile portrayed nurse Rose, a love interest for Derek. Former regular Kate Walsh appeared for the first time since her departure on May 1, 2008 receiving a special guest star billing in the role of Addison Montgomery, now the main character of the spin - off Private Practice. Jeff Perry, Loretta Devine and Debra Monk reprised their roles as Thatcher Grey, Adele Webber and Louise O'Malley, respectively. Diahann Carroll and Elizabeth Reaser continued their season three - introduced roles as Jane Burke and Rebecca Pope, respectively. In October 2006, news reports surfaced that Washington had insulted co-star T.R. Knight with a homophobic slur during an argument with Patrick Dempsey. Shortly after the details of the argument became public, Knight publicly disclosed that he was gay. The situation seemed somewhat resolved when Washington issued a statement, apologizing for his `` unfortunate use of words during the recent incident on - set. '' The controversy later resurfaced when the cast appeared at the Golden Globes in January 2007. While being interviewed on the red carpet prior to the awards, Washington joked, `` I love gay. I wanted to be gay. Please let me be gay. '' After the show won Best Drama, Washington, in response to press queries as to any conflicts backstage, said, `` I never called T.R. a faggot. '' However, in an interview with Ellen DeGeneres on The Ellen DeGeneres Show, Knight said that `` everybody heard him. '' After being rebuked by his studio, Touchstone Television, Washington issued a statement apologizing for repeating the word on the Golden Globes carpet. On January 30, 2007, a source told People magazine that Washington was scheduled to return to the Grey 's Anatomy set as early on that Thursday for the first time since entering `` executive counseling '' after making the comments at the Golden Globes. However, on June 7, 2007, ABC announced it had decided not to renew Washington 's contract, and that he would be dropped from the show. `` I 'm mad as hell and I 'm not going to take it anymore, '' Washington said in a statement released by his publicist, borrowing the famous line from Network. In another report, Washington stated he was planning to `` spend the summer pursuing charity work in Sierra Leone, work on an independent film and avoid worrying about the show. '' In a subsequent interview, Washington claimed that `` they fired the wrong guy '', referring to Knight, and said he was considering filing a lawsuit as a result. He accused Knight of using the controversy to bolster his own career and increase his salary on Grey 's Anatomy. Washington, in late June 2007, began asserting that racism within the media was a factor in his firing from the series. On July 2, 2007, Washington appeared on Larry King Live on CNN, to present his side of the controversy. According to Washington, he never used the `` F Word '' in reference to Knight, but rather blurted it out in an unrelated context in the course of an argument `` provoked '' by Dempsey, who, he felt, was treating him like a `` B - word, '' a `` P - word, '' and the `` F - word, '' which Washington said conveyed `` somebody who is being weak and afraid to fight back. '' Washington himself said that his dismissal from Grey 's Anatomy was an unfortunate misunderstanding that he was eager to move past. He later stated that if he were to be asked to make a cameo appearance on the show, he would not hesitate to say `` yes ''. Washington 's image was used in advertisements for the May 9, 2008 episode `` The Becoming ''. After this aired, Washington 's attorney Peter Nelson contacted ABC and Screen Actors Guild and cited this as an unlawful use of his client 's image. His publicist, Howard Bragman, told The Hollywood Reporter that `` they have the rights of the character to advance the story, but not the image '' and stated he expected this to result in a `` financial settlement '', but it is still uncertain whether this ultimately happened. Reception Heigl refused to be considered for the 2008 Emmy Awards due to insufficient material on Grey 's Anatomy. Debbie Chang of BuddyTV.com expressed disappointment in the shows ' development throughout the season, by stating it was `` all about couples, jumping in and out of relationships, trying their darnedest to have hot sex on the cramped, twin - sized bunk - beds in the on - call room ''. Chang also noted the little screen time of characters Mark Sloan and Richard Webber, and the lack of romantic development in their storylines. Many critics negatively reviewed Izzie Stevens 's development in the show 's fourth season, particularly her affair with George. Katherine Heigl herself deemed their relationship `` a ratings ploy ''. Heigl explained : `` They really hurt somebody, and they did n't seem to be taking a lot of responsibility for it. I have a really hard time with that kind of thing. I 'm maybe a little too black and white about it. I do n't really know Izzie very well right now. She 's changed a lot. '' Laura Burrows of IGN stated the series became `` a little more than mediocre, but less than fantastic '' in its fourth season. She also said that `` this season proved that even strong chemistry and good acting can not save a show that suffers from the inevitable recycled plot. '' However, the episode `` Physical Attraction, Chemical Reaction '' received a positive review, with Burrows stating that it `` fully encompassed all the things that make this show great : intense emotional drama and macabre OR activities ''. The Derek / Rose relationship received negative reviews, with Burrows stating that it was `` emotional, but not remarkable ''. Jack Florey of IndieLondon reviewed the characters, stating that their behaviour is the show 's biggest problem : `` the self - absorbed, pretentious and frequently selfish attitudes that drive the surgeons at the centre of Grey 's exasperate more than reward. '' As for the storylines, Foley stated that they did n't `` ring true '' and that `` the plot devices became increasingly clunky '', noting the lack of realism in arcs such as George and Callie 's marriage and the Izzie 's affair `` as a means of ripping it apart ''. Florrey also commented on Meredith Grey 's arc, by stating that she turned into `` one of the most selfish, self - centered characters on television '', whereas Mark Sloan 's storyline was named `` sex - obsessed, borderline misogynistic and close to scandalous ''. Daniel Fienberg of Zap2It said `` One of the season 's best performances came from Emmy - nominated guest star Elizabeth Reaser. '' Pajiba TV reviewed Reaser 's performance by stating that it `` has been one of the only good things that show 's had going for it anymore. '' Entertainment Weekly called Reaser 's performance as Ava the sixth most memorable patient performance on the show. About.com stated that Alex Karev developed into `` a bold and overly confident surgeon ''. Several actors and members of the production team have been awarded for their work on the show during the season. At the 60th Primetime Emmy Awards on September 21, 2008, Sandra Oh was nominated for her performance as Cristina Yang in the episode `` The Becoming '', whereas Chandra Wilson received a nomination for her portrayal of Miranda Bailey in `` Lay Your Hands on Me '', both for the Outstanding Supporting Actress in a Drama Series. Katherine Heigl who portrayed Izzie Stevens declined to put her name forward for consideration at the Emmy Awards, claiming that she had been given insufficient material on the series to warrant a nomination. Diahann Carroll was nominated for Outstanding Guest Actress in a Drama Series for her portrayal of Jane Burke in `` Love / Addiction ''. The make - up team, consisting of Norman T. Leavitt, Brigitte Bugayong, Thomas R. Burman and Bari Dreiband - Burman, was nominated for both Best Prosthetic Make - Up in `` Forever Young '' and Best Non-Prosthetic Make - Up in `` Crash Into Me ''. Sara Ramirez 's portrayal of Callie Torres was positively reviewed, resulting in her receiving a nomination at the 2008 American Latino Media Arts Awards. At the 65th Golden Globe Awards in January 13, 2008, the series was nominated for Best Drama Television Series, whereas Katherine Heigl 's individual performance resulted in a nomination for Best Supporting Actress in a Television Series. At the 40th National Association for the Advancement of Colored People Image Awards, Chandra Wilson won Outstanding Actress in a Drama Series, where Shonda Rhimes was awarded at the Outstanding Writing in a Dramatic Series category, for `` Freedom ''. James Pickens, Jr. also received a nomination for his performance as Richard Webber at the Outstanding Supporting Actor in a Drama Series category. At the 2008 Prism Awards, Justin Chambers was nominated for Performance in a Drama Series Episode, whereas Elizabeth Reaser received a nomination for Performance in a Drama Multi-Episode Storyline. At the Teen Choice Awards in 2008, Patrick Dempsey and Katherine Heigl were nominated for Choice Television Actor and Actress. The season was the second to air in the Thursday night time slot, at 9 : 00 ET, after it was moved at the beginning of the third season, following two seasons in the Sunday night timeslot, as a lead - out to Desperate Housewives, which aired at 9 : 00 ET for its entire run. The season aired as a lead - out to Ugly Betty, then in its second season, which aired on Thursday nights at 8 : 00 ET. Grey 's Anatomy averaged 15.92 million viewers in its fourth season, ranking tenth in viewership. The highest - rated episode of the season was the season premiere, with 20.93 million viewers tuning in and a 7.3 rating, ranking the third for the week. The episode showed a decrease in ratings compared to the previous season premiere, which had almost five more million viewers tuning in and a 9.0 rating. The season premiere also attracted less viewers than the previous season finale, which was watched by 22.57 million viewers, and received an 8.0 rating Although `` A Change is Gonna Come '' attracted more viewers than Desperate Housewives 's `` Now You Know '', which was watched by 19.32 million viewers, received a 6.7 rating and ranked fourth in the week, the episode was outperformed by CSI : Crime Scene Investigation 's `` Dead Doll '', which aired in the same hour and ranked first in the week, with 25.22 million viewers tuning in and an 8.8 rating. The lowest - rated episode was the ninth, watched by 14.11 million viewers and ranked fourteenth in the week, with a 4.9 rating, seeing a sudden decrease, after the previous episode, the second most - watched in the season, which attracted 19.61 million viewers and received a 6.8 rating. `` Crash Into Me : Part 1 '' was outperformed in the time slot by CSI : Crime Scene Investigation 's `` You Kill Me '', the Thanksgiving special episode which attracted 14.75 million viewers and received a 5.2 rating, ranking eleventh in the week. The season finale was watched by 18.09 million viewers, being the first - season finale of Grey 's Anatomy to attract less than 20 million viewers. It was ranked fifth in the week, and received a 6.3 rating. There was a significant decrease in the number of viewers, compared to the previous season finale, which attracted almost four more million viewers and received an 8.0 rating. Episodes Main article : List of Grey 's Anatomy episodes No. overall No. in season Title Directed by Written by Original air date U.S. viewers ( millions ) 62 `` A Change Is Gonna Come '' Rob Corn Shonda Rhimes September 27, 2007 ( 2007 - 09 - 27 ) 20.93 Having just returned from her honeymoon with Meredith, Cristina searches for Burke, but he is nowhere to be found. Meredith, Cristina, Izzie and Alex spend their first day as residents with their own groups of interns. Among the interns are George, repeating his intern year after failing his exams, and Lexie Grey, Meredith 's half - sister whom she has never met. The residents and interns have to deal with the victims of a multi-car pile - up, including a man who came to life, a pregnant woman who lost an arm, and a man with a compulsive desire to eat. Izzie attracts her interns ' ire by having them treat a deer. Now that Derek 's relationship with Meredith has reached an emotional impasse, he looks to his fellow doctors for friendship. Webber resumes his position as Chief of Surgery. Bailey wrestles with her place within the hospital now that her former interns report to new Chief Resident Callie, who struggles with her new position. 63 `` Love / Addiction '' James Frawley Debora Cahn October 4, 2007 ( 2007 - 10 - 04 ) 18.51 An apartment explosion inundates the ER with patients, and Alex jeopardizes a family when he realizes the cause of the accident. Meanwhile, Meredith intrigues Derek with an `` S&M '' ( sex and mockery ) approach on their relationship, and Derek gets the wrong idea. Cristina begins giving her wedding gifts to her colleagues in exchange for surgeries. Mama Burke returns to collect Burke 's things, and gives judgement and advice to the doctors. George decides to break up with Callie after realizing that he has feelings for Izzie, but Izzie stops him when she has to work with Callie, and sees how she 's struggling. Callie clashes with Bailey after she sends Meredith to the clinic after becoming annoyed with Lexie and another intern. Meredith rebuffs Lexie 's attempts to get to know her. Webber begins delegating in a bid to get back with Adele. 64 `` Let the Truth Sting '' Daniel Minahan Mark Wilding October 11, 2007 ( 2007 - 10 - 11 ) 19.04 When the `` really old guy '' awakens from his coma, Izzie becomes aggravated with him over his attempts to end his life. Izzie puts pressure on George to end things with Callie. Callie and George find themselves both very tense in their hotel room. Bailey confronts Callie over the amount of effort that she is putting in as Chief Resident. Meredith and Lexie 's rocky relationship continues because of Meredith 's teaching technique, but Bailey intervenes in order to help Lexie develop. Cristina begins faking sadness to get more surgeries. Alex gets a new intern, Norman, and is forced to do a procedure he 's unfamiliar with on a patient when Derek becomes unavailable. Mark and Webber attempt a surgery neither has performed before, and Derek has to remind them of the risk they took. Alex tells the other interns that George is repeating his internship. 65 `` The Heart of the Matter '' Randall Zisk Allan Heinberg October 18, 2007 ( 2007 - 10 - 18 ) 18.04 Meredith agrees to go away with Derek for the weekend, but has to take Norman off of Alex. However, Derek realizes that he and Meredith want different things, and considers ending their relationship. Meredith gets annoyed at Norman after his error leads to them telling the wrong patient that she 's dying. Callie forgives George for sleeping with Izzie. Lexie stands up to Cristina, and Derek criticizes her teaching style. George desperately tries to find Izzie before Callie can, while Izzie admits to Alex that she slept with George. Derek, Cristina and Lexie treat a college football player who faces paralysis, whose dad is still heavily critical of him. Bailey and Callie have to deal with a patient who wants to leave the hospital as quickly as possible so she can continue training to earn the approval of her boyfriend, and Callie takes her personal issues out on him when the patient dies. Webber 's niece ends up back in the hospital, and Webber is disheartened when she admits that she does n't want further cancer treatment. 66 5 `` Haunt You Every Day '' Bethany Rooney Krista Vernoff October 25, 2007 ( 2007 - 10 - 25 ) 18.17 A nightmare brings Meredith to remove her mother 's ashes from her closet. She ends up putting her mother at rest in an operating theatre sink. Meredith also forms an alliance with a little boy to grant him the ears he needs via pro-bono surgery. Alex ignores Norman feeling unwell, which culminates with Norman suffering a stroke. A busy day in the ER results in a man who is convinced that his foot does n't belong to him trying to remove it with a chainsaw from a jack - o - lantern competition. A heart transplant patient has to face a difficult decision when his daughter is in an accident and rendered brain dead, meaning that her heart has become available to him. Rebecca seeks out Alex. Erica Hahn is invited to perform a heart transplant, and clashes with Cristina. Callie reveals George 's affair with Izzie to the hospital. Callie and Cristina bond over their failed relationships, prompting Cristina to invite Callie to move in. 67 6 `` Kung Fu Fighting '' Tom Verica Stacy McKee November 1, 2007 ( 2007 - 11 - 01 ) 19.31 Webber organizes a gentleman 's evening, leaving Derek and Mark dumbfounded, and curious to determine what it really is. Two brides - to - be fight over a dress from a bridal store competition, and this complicates treatment, as neither will release the dress. The doctors treat a parachutist who fell 12,000 feet without a parachute. Callie searches for a way to torture George whilst trying to cope with the stress from her Chief Resident position and impending divorce. Meredith tries getting Cristina to diagnose her personal problems. Izzie prepares to sleep with George for the first time in their new relationship. Erica excludes Cristina from cardio service, which drives Cristina insane and desperate, especially when Erica has Izzie scrub in on an awake open - heart surgery. Alex takes pity on Lexie when he catches her charting in a cupboard, and they eventually sleep together. 68 7 `` Physical Attraction, Chemical Reaction '' Jeff Melman Tony Phelan & Joan Rater November 8, 2007 ( 2007 - 11 - 08 ) 19.50 Izzie and George 's new - founded relationship results in bad sex. Callie shirks her Chief Resident responsibilities and the position is taken away from her, with Bailey as the humble replacement. Meredith continues to struggle with her relationship with Lexie. Cristina is annoyed when Erica swaps her with Meredith, and is then told by Bailey to look for a different specialty. Cristina 's woes are worsened when Erica and Meredith take her patient off of her. Both Izzie and Alex have to deal with patients that are annoying them, and get unexpected results when they put them in the same room. George and Bailey operate on an eight - year - old who has taken drastic action following his parents ' marital difficulties. Derek finds himself doing chores for Webber, who does n't know how to be on his own. 69 8 `` Forever Young '' Rob Corn Mark Wilding November 15, 2007 ( 2007 - 11 - 15 ) 19.61 A bus crash involving high school students causes the doctors to reminisce about their times in high school. Bailey sets out her rules as Chief Resident. A tense confrontation between Lexie and Meredith brings Meredith to feel guilty. Callie gives Cristina some tips to get on Erica 's good side when she notices Cristina trying to impress her. An old flame of Bailey 's emotional when he arrives in the ER, and Bailey and Erica clash over how she is with him. Izzie bonds with a teenager, while Derek treats her best friend, who got a pencil jammed in his eye socket in the crash. Mark and Callie have to deal with a victim who wants perfection from them. The news about Izzie and George 's relationship problems travels fast around the hospital, and they worsen after Izzie catches wind of people gossiping about them. Thatcher Grey injures himself and requests to be treated by Meredith. Derek meets a nurse, Rose, who appears to be interested in him. 70 9 `` Crash Into Me ( Part 1 ) '' Michael Grossman Shonda Rhimes & Krista Vernoff November 22, 2007 ( 2007 - 11 - 22 ) 14.11 An ambulance crash makes for a hectic day at Seattle Grace, when Meredith and Webber have to comfort the paramedics trapped inside one of the ambulances. A wounded paramedic creates an uproar in the ER over his tattoo, offending Bailey. As she operates on him she has the other doctors swear not to use her alias anymore. Derek and George treat the driver who caused the accident, and find a brain tumor. Derek and Rose get to know each other better. Bailey faces relationship troubles over how much time she spends at the hospital. Callie, Mark and Erica have to operate on a heart patient who was injured in the crash. Lexie becomes attached to a patient ( Seth Green ), who has a major artery exposed following the removal of a tumor. Rebecca returns and Lexie finds out Alex has been seeing them both. 71 10 `` Crash Into Me ( Part 2 ) '' Jessica Yu Shonda Rhimes & Krista Vernoff December 6, 2007 ( 2007 - 12 - 06 ) 17.78 Meredith works to save the life of a paramedic, after his colleague died. Meredith asks Derek not to see other people after taking inspiration from some advice Webber gave a patient. Derek has to rely on Rose after the camera monitor breaks during the middle of a surgery, which leads to the pair sharing a kiss. Alex is suspended for a week for sneaking Rebecca in to observe a surgery. Izzie realizes that she is not cut out for cardio surgery. Tensions between Bailey and Tucker reach a breaking point. Cristina takes pity on Lexie, after her actions lead to the death of a patient. 72 11 `` Lay Your Hands on Me '' John Terlesky Allan Heinberg January 10, 2008 ( 2008 - 01 - 10 ) 17.68 When Bailey 's son, Tuck, is at Seattle Grace following a bookshelf falling on him, she starts to feel that she might be a bad mother. Tucker and Bailey separate. The return of George 's mother brings Callie and George together once more, and his relationship with Izzie has failed. Izzie and Cristina continue their rivalry, and Izzie later admits to Alex that it is based on jealousy. A healer with `` powers '' at Seattle Grace makes the doctors question science and faith. Meredith discovers Rose and Derek have kissed, which leads to them breaking up. Lexie suffers an allergic reaction after Meredith makes her breakfast. 73 12 `` Where the Wild Things Are '' Rob Corn Zoanne Clack April 24, 2008 ( 2008 - 04 - 24 ) 16.37 Six weeks have passed since Derek started dating Rose, and the new residents are competing in a surgical contest. Meredith wins, giving her the power to take the other residents ' surgeries. Izzie treats a man with a swollen ankle who collapsed, as she believes that he has a mystery illness. The doctors treat a family who were all victims of a bear attack. Meredith thinks that one of the victims might be suffering from a neurological disorder, but she is brushed off by others who think she 's just trying to get an opportunity to be with Derek. George and Lexie have moved into their new apartment and Lexie begins stealing stuff from the hospital to furnish it. Callie and Erica continue their friendship. Meredith suggests a neurological clinical trial. 74 13 `` Piece of My Heart '' Mark Tinker Stacy McKee May 1, 2008 ( 2008 - 05 - 01 ) 15.31 Addison Montgomery visits Seattle Grace from California and she is recapped by the doctors on what has happened in her absence. She suspects that Callie might be having feelings for Erica. The surgeons deal with a mother whose baby 's heart has developed outside of his chest, and Mark becomes a bit too pompous when he feels like he is God. Izzie is jealous that George is developing a good relationship with his fellow interns. Rebecca reveals she is pregnant. Izzie is shocked when her pregnant patient wants an abortion, but both eventually regain their ability to fight. Meredith is conerned after the patient in her clinical trial goes blind. Erica finally tells Cristina why she wo n't teach her. 75 14 `` The Becoming '' Julie Anne Robinson Tony Phelan & Joan Rater May 8, 2008 ( 2008 - 05 - 08 ) 16.03 A `` date and tell '' policy is instated at Seattle Grace after the nurses object to Mark 's trysts, causing everybody in the hospital to have to register their relations with one another. Lexie is concerned to find out Alex forgot to register their night together. Webber comes face to face with Adele again. News of Burke winning an award reaches the hospital, unsettling both Cristina and Erica. Callie starts having sex with Mark to avoid Erica. Meredith and Derek admit a gay veteran soldier into their clinical trial. George is given the title ' Intern to the Chief '. Alex starts moonlighting at Joe 's, so he can get money for a house for him and Rebecca. Meredith 's therapist gets tough. 76 15 `` Losing My Mind '' James Frawley Debora Cahn May 15, 2008 ( 2008 - 05 - 15 ) 15.55 Meredith 's therapy leads herself to question her past. Derek and Meredith 's are at loggerheads when a patient in their clinical trial wants to delay treatment to wait for her boyfriend, whom her sister insists does n't exist. Callie begins to wonder if she is straight or lesbian, and she tries to avoid the topic. Mark tries shaking off his `` whore '' image, by trying to get emotional with Callie. Webber 's mentor arrives at the hospital requiring treatment, but Erica is reluctant to operate on a legend. Cristina is lashing out, and eventually Lexie bites back. Izzie tries to tell Alex that Rebecca is not pregnant. 77 78 16 17 `` Freedom '' Rob Corn Shonda Rhimes May 22, 2008 ( 2008 - 05 - 22 ) 18.09 A surgical team battles the clock as they try to save a boy encased in cement. Alex 's situation with an ever - disintegrating Rebecca brings back painful memories that interfere with his judgment. Derek and Meredith have one last chance at their clinical trial. The parents of one of the patients want Derek and Meredith to move the other patient in the trial elsewhere. Lexie looks at the residents ' case files. Meredith gives the `` sparkle pager '' to Cristina, to help her cope with her depression. Derek and Meredith 's relationship becomes more fractured as Meredith tries to push for the surviving patient to have the clinical trial. However, when the trial has a positive outcome, Derek and Meredith decide to restart their relationship. Izzie is concerned when Alex tries to treat Rebecca after she slit her wrists. After Bailey sees Izzie struggling, she gives her the clinic. Mark ends his relationship with Callie, which leads to Erica and Callie kissing. Webber prepares to win back Adele, and move back in with her. A boy trapped in cement after a dare has placed his health at risk, leading the doctors at Seattle Grace to sympathize and ease his pains. Cristina takes the lead in surgery. George confronts Webber, and is allowed to retake the internship test. George later kisses Lexie in joy, but is unaware that she is harboring feelings for him. DVD Release The fourth season was officially released on DVD in region 1 on September 9, 2008, almost three weeks before the fifth season premiere, which aired on September 25, 2008. Under the title Grey 's Anatomy : Season Four -- Expanded, the box set consists of episodes with Dolby Digital 5.1 surround sound and widescreen format. It also contained extras available only on DVD, including extended episodes, interviews with cast and crew members, footage from behind the scenes and unaired scenes cut from the aired episodes. The same set was released in region 4 on November 5, 2009, after more than a year after its original release in the United States, whereas its first release date in region 2 was November 23, 2009. The DVD box set is currently no. 1074 in Movies and Television on Amazon.com and no. 1927 in Film and Television on Amazon.co.uk. The season was also released as a five - disc Blu - ray box set in regions A and B. The Blu - ray release proved unsuccessful and is currently no. 39614 in Movies and Television on Amazon.com Grey 's Anatomy : The Complete Fourth Season -- Expanded Set Details Special Features 17 episodes ( 1 extended ) 5 - disc set 1.78 : 1 aspect ratio English ( Dolby Digital 5.1 Surround ) Subtitles : English, French, Spanish Audio Commentaries Extended Episode `` Forever Young '' New Docs on the Block -- Interview with Brooke Smith, Chyler Leigh and Lauren Stamile On Set with Patrick & Eric -- Behind the Scenes with Patrick Dempsey and Eric Dane Good Medicine -- Favorite Scenes Dissecting Grey 's Anatomy -- Unaired Scenes Bloopers Release Dates Region 1 Region 2 Region 4 September 9, 2008 November 23, 2009 November 5, 2008 References ^ Jump up to : `` Writers strike could pull plug on TV favorites ''. MSNBC. Retrieved 26 May 2012. Jump up ^ `` ABC Renames Television Studio ''. ABC. Walt Disney. February 8, 2007. Retrieved May 10, 2012. 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Jump up ^ Jackson 's TV Comeback Derailed By Strikes, TeenTelevision.com, December 14, 2007 Jump up ^ `` ' Grey 's Anatomy ' Casts Mystery Woman ''. Zap2it. Tribune Company. October 5, 2007. Retrieved August 21, 2012. Jump up ^ `` EXCLUSIVE : Isaiah Washington Apologizes ''. People. Time Inc. October 25, 2006. Retrieved May 29, 2012. Jump up ^ The Associated Press ( January 17, 2007 ). `` Isaiah Washington : `` I Love Gay '' ``. Access Hollywood. Archived from the original on January 20, 2007. Retrieved 2007 - 01 - 17. ^ Jump up to : `` ABC rebukes ' Grey 's Anatomy ' star for slur ''. MSNBC. January 22, 2007. Retrieved May 29, 2012. Jump up ^ `` Knight : Isaiah Forced Me Out with `` Faggot '' Slur ``. TMZ. Time Warner. January 17, 2007. Retrieved May 29, 2012. Jump up ^ `` Bad News : Rehab Does Not Cure Anti-Semitism ''. Jezebel. Gawker Media. Retrieved May 29, 2012. Jump up ^ Finn, Natalie ( June 7, 2007 ). `` Isaiah Washington Fails Anatomy, `` Mad as Hell '' ``. E ! Online. NBCUniversal. Archived from the original on July 16, 2012. Retrieved May 29, 2012. Jump up ^ `` ABC drops Washington from Grey 's Anatomy ''. Cbc.ca. June 8, 2007. Archived from the original on June 11, 2007. Retrieved June 8, 2007. ^ Jump up to : `` Troubled Actor Isaiah Washington Outlines Post-TV Plans ''. starpulse.com. Retrieved May 29, 2012. Jump up ^ `` Racism was a factor ''. The Washington Post. The Washington Post Company. June 29, 2007. Retrieved May 29, 2012. Jump up ^ For the transcript, see http://transcripts.cnn.com/TRANSCRIPTS/0707/02/lkl.01.html Jump up ^ Simmons, Leslie ( May 11, 2008 ). `` Actor Washington files complaint over ' Anatomy ' ''. Reuters. Retrieved October 8, 2008. ^ Jump up to : Chang, Debbie ( January 28, 2008 ). `` Grey 's Anatomy : Season 4 in Review ''. BuddyTV. Retrieved May 26, 2012. ^ Jump up to : Bennetts, Leslie ( January 2008 ). `` Heigl 's Anatomy ''. Vanity Fair. Condé Nast Publications. 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Grey 's Anatomy episodes Season 1 `` A Hard Day 's Night '' `` If Tomorrow Never Comes '' Season 2 `` Into You Like a Train '' `` It 's the End of the World '' `` As We Know It '' `` Losing My Religion '' Season 3 `` Time Has Come Today '' `` I Am a Tree '' `` Great Expectations '' `` Wishin ' and Hopin ' '' `` Did n't We Almost Have It All ? '' Season 4 `` A Change Is Gonna Come '' Season 5 `` Stand By Me '' `` Elevator Love Letter '' `` What a Difference a Day Makes '' `` Now or Never '' Season 6 `` Good Mourning '' `` Goodbye '' `` I Always Feel Like Somebody 's Watchin ' Me '' `` Tainted Obligation '' `` Invasion '' `` I Saw What I Saw '' `` Give Peace a Chance '' `` Invest in Love '' `` I Like You So Much Better When You 're Naked '' `` Death and All His Friends '' Season 7 `` Song Beneath the Song '' Season 8 `` Flight '' Season 9 `` Going, Going, Gone '' `` Beautiful Doom '' `` Perfect Storm '' Season 10 `` Fear ( of the Unknown ) '' Season 11 `` I Must Have Lost it on the Wind '' `` Puzzle with a Piece Missing '' `` Got to Be Real '' `` Only Mama Knows '' `` Bend & Break '' `` Do n't Let 's Start '' `` One Flight Down '' `` How to Save a Life '' `` She 's Leaving Home '' `` Time Stops '' `` You 're My Home '' Season 12 `` Sledgehammer '' `` Guess Who 's Coming to Dinner '' `` Something Against You '' `` Things We Lost in the Fire '' `` The Sound of Silence '' `` Family Affair '' Season 13 `` True Colors '' Season 14 `` Danger Zone '' `` Personal Jesus '' `` All of Me '' Season 15 Grey 's Anatomy Episodes Season 1 5 6 7 8 9 10 11 12 13 14 15 Characters ( cast members ) Meredith Grey Cristina Yang Izzie Stevens Alex Karev George O'Malley Miranda Bailey Richard Webber Preston Burke Derek Shepherd Addison Montgomery Callie Torres Mark Sloan Lexie Grey Erica Hahn Owen Hunt Sadie Harris Arizona Robbins Teddy Altman Jackson Avery April Kepner Amelia Shepherd Stephanie Edwards Maggie Pierce Nathan Riggs Jo Wilson Karev Spin - offs Private Practice Station 19 Other Awards and nominations Soundtrack Video game A Corazón Abierto ( Mexican telenovela ) A Corazón Abierto ( Colombian telenovela ) Portal Wikiquote has quotations related to : Grey 's Anatomy ( season 4 ) Retrieved from `` https://en.wikipedia.org/w/index.php?title=Grey%27s_Anatomy_(season_4)&oldid=858219518 '' Categories : Grey 's Anatomy episodes 2007 American television seasons 2008 American television seasons Grey 's Anatomy seasons Hidden categories : Good articles Talk Contents About Wikipedia Deutsch Español Français Italiano Polski Português Edit links This page was last edited on 5 September 2018, at 20 : 10 ( UTC ). 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Question: why do meredith and derek break up in season 4
Answer: Rose and Derek have kissed