Izzie and Meredith are assigned to assist Erica Hahn with a heart patient and Izzie freaks out when she realizes that she’s now helping take care of the man who was supposed to get the heart she stole for Denny. That’s right, she stole a donor heart for Denny Duquette, trying everything she could to save the man she loved, and this poor guy has paid the price. Now this patient has to undergo an excruciating experimental procedure and Izzie’s assigned to help him through it, since she’s the best at relating to patients. Suddenly, whether it’s brought on by stress or memories or something else, Izzie actually starts seeing Denny and she’s unable to do her job effectively.
Derek can’t get a wink of sleep because Meredith and Cristina are always having girl talk late at night. He comes up with a cunning plan: he tries to convince Mark Sloan, who’s pretty much slept with every available woman (and some of the unavailable ones, too), at Seattle Grace, to hook up with Cristina. At first, Mark’s not interested, but when he gives it a shot and Cristina laughs, he sees it as a challenge and lays on the charm.
The residents are doing everything they can to win a solo surgery, and George gets stuck taking care of “Stan,” a robotic dummy that he can practice on. What George doesn’t know is that the Chief is controlling the robot and is having the time of his life berating O’Malley with the robot and piling on medical complications.
Lexie’s disgusted when she finds the other interns practicing simple procedures on each other, and we can’t blame her. She thinks she has a brilliant idea when she grabs bodies in the morgue and the other interns finally have something to work with besides themselves. Unfortunately, they get found out by the residents and are promptly kicked out while Cristina, Meredith, Alex and the others start practicing on the bodies themselves!
Owen’s not impressed by the vulture-like behavior of the residents, and he calls Cristina and Alex to the carpet for it. He tells Cristina that if she’s in medicine to win competitions, she needs to stop being a doctor. She finds him later and tells him why she became a doctor: when she was nine years old she sat with her dying father after a car accident and felt his heart stop. After that, Owen starts to see something to Derek’s comment comparing Cristina to a single malt scotch.
Erica is enraged to find out the part Izzie played in Denny's acquiring the heart intended for her patient and storms into Richard's office. Richard tells her not to stir up the past, so instead, she orders a guilt-ridden Izzie to sit with the patient through another difficult procedure and face up to her responsibility for his situation. Izzie commits to talking him through the pain this time, under Denny's approving eye. After the procedure is a success, she looks up and Denny is no longer there.
Erica tells Callie she intends to report Izzie to a medical review board and is shocked when Callie sides with Izzie and Richard. "There is no gray area here," Erica insists. "You can't kind of side with Izzie Stevens. And you can't kind of be a lesbian. I don't know you at all," she says, and walks away.