<P> Speculation resumed, however, when Dean Morgan returned to the show for a second time in its fifth season . Cast member James Pickens, Jr. announced that both Heigl and T.R. Knight were set to depart from the show, but he later retracted his comment . During the course of the fifth season, Izzie was diagnosed with metastatic melanoma (Stage IV) which spread to her liver, skin and brain . Following the show's one - hundredth episode wrap party, Heigl revealed she did not know if Izzie would survive, as no one on the production team would disclose her character's fate to her . It was confirmed in June 2009 that Heigl would return as Izzie for the show's sixth season . Heigl's appearances in the season were sporadic, seeing Izzie depart and return twice . Although she was scheduled to appear in the final five episodes of the season, Heigl requested that she be released from her contract 18 months early, and made her final appearance on January 21, 2010 . Heigl explained that she wanted to spend more time with her family, and did not think it would be respectful to Grey's Anatomy viewers to have Izzie return and depart yet again . Michael Ausiello spoke further on Katherine Heigl's perspective on Izzie's departure . He said, "(Katherine) thinks her Jan. 21 farewell - while not originally intended to be her last episode - oddly works as a bookend to Izzie's story . "Even though there's a part of me that would like to go back and do the quick Izzie farewell," she says, "I also think that my last scene - where Meredith says to Izzie,' Don't go, we're your family,' and Izzie's response was,' No you're not, you're just a bunch of people I worked with, and I can find that anywhere' - was kind of tragic and appropriate all at the same time . When I was playing the scene I was really trying to convey that, for Izzie, that was a lie that she had to tell herself to have the courage to have to move on ." </P> <P> In August 2010, Rhimes stated that she did not feel Izzie's character arc--specifically her relationship with Alex--had fully concluded, and hoped to give proper closure to their relationship in the seventh season . She later confirmed that she had intended to kill off Izzie off - screen, but opted against this a day later as she felt that it would destroy Alex, rather than give him closure . Instead, she concluded: "I'm open to seeing Izzie again . So if she (Katherine) were to come back, we would be thrilled to (wrap up her story). But if she doesn't, we'll just move on ." Heigl also went on to say in October 2010 that the character returning to show looks bleak because, "that chapter is closed, and it's sad . And it's hard ." She also felt that Izzie coming back to the show would, "just feel manipulative ." </P> <P> However, in January 2012, Heigl stated in an interview that she has asked the producers if she could return to the show to give closure to Izzie's storyline: "I've told them I want to (return)," she said . "I really, really, really want to see where (Izzie) is . I just want to know what happened to her and where she went and what she's doing now . My idea is that she actually like figures it out, and finds some success and does really well in a different hospital . She was always floundering you know, and so she was always one step behind the eight ball and I want to see that girl take some power back ." She later went on to say that she regrets leaving the show, "Oh yeah, sometimes, yeah . You miss it . I miss my friends . It was a great work environment...and it becomes a family . I spent six years together with these people every day...you grow up together, in a way," and again commented on Izzie possibly returning to the show, "I always felt that if they wanted me to come back and sort of wrap up that storyline...I want them to know that I'm down with it if they want me to, but I completely understand if it doesn't necessarily work...They've got a lot of story lines going on there ." But in March 2012, Shonda Rhimes said that there are no plans at the moment for the character to return, "I think it was really nice to hear her appreciating the show . At the same time we are on a track we have been planning . The idea of changing that track is not something we are interested in right now ." Three years later, Rhimes said she has completely moved on from the idea of Izzie coming back, "I'm done with that story . I've turned that idea over in my mind a thousand times and thought about how it would go . And I don't think so ." </P> <P> Heigl believes that the Grey's Anatomy writers incorporate much of the actors' personalities into their roles, and that Izzie is a "super moral" version of herself . Episode "Bring the Pain", which aired as the fifth episode of the second season, was originally intended to be the final episode of the first season . Rhimes explained that Izzie's character in this episode came "full circle" from her role in the pilot: "Izzie, so vulnerable and underestimated when we first meet her, is the girl who removes her heart from her sleeve in "Bring the Pain"." Discussing Izzie's personality in a 2006 Cosmopolitan interview, Heigl assessed that she is "immensely kind" and patient . When Denny died in the season two episode "Losing My Religion", Rhimes discussed the impact it had on Izzie, noting that Izzie is forced to abandon her idealism, which in turn leads to her letting go of medicine . In the aftermath of Denny's death, Heigl came to believe that Izzie was not cut out to be a doctor . Executive producer Betsy Beers explained, however, that Denny's death served to make Izzie more mature, and Heigl affirmed that "At the beginning of the (third) season they were trying to show how lost Izzie was . She lost her optimism . She realizes now that life is difficult, but she still tries very hard to see the best in people ." In order to demonstrate Izzie's dislike of George's love - interest Callie, Rhimes penned a scene which she deemed one of her favorite moments on the show, in which Callie urinates in front of a stunned Izzie and Meredith . Rhimes assessed that: "I love that Mer and Izzie respond with all the trauma of having viewed a car crash (...) the point is Callie pees and Izzie tortures her a tiny bit about the hand washing and that made me overjoyed because that's the kind of thing people do ." </P>

What episode does george and izzie sleep together