Izzie and Meredith are assigned to assist Erica with a heart patient and Izzie is distraught when she realizes who the man is. "That's the heart I stole for Denny," she tells Meredith. The fact that the patient is in Denny's old room makes it even worse. "That's a lot of Denny," Meredith admits, but she isn't seeing him walking the hallways, like Izzie is. Izzie's duty during an experimental procedure -- during which the patient will be awake -- is to talk the man through the excruciating pain he's experiencing. Erica selected her because of her ability to bond with patients, but Izzie is seeing Denny in the O.R. and can't breathe. "I'm so sorry," she says and runs out.
Meredith reveals that Izzie's connection to Denny Duquette, a name Erica knows all too well as she was the surgeon who performed the surgery.
Derek is annoyed with Cristina for her late-night chats with Meredith, which rob him of sleep, so he has a favor to ask of Mark. "I need you do have sex with Cristina Yang. Distract her." Mark declares her "unfun" and "not my type," but Derek reminds him. "You slept with my wife," and Mark sighs and says, "Yeah, I'll give it a shot." Mark tries his best, but Cristina laughs when she realizes he's been unsuccessfully flirting with her all day.
The residents are abuzz when they learn that the winner of the skills lab will be awarded a solo surgery. George gets stuck with "Stan," a robotic patient who can talk about his symptoms, much to his frustration as the robot says things like, "I can't believe you passed your intern exam!" George is finally triumphant in saving Stan's life but not sure how to feel when he realizes he's been verbally abused by Richard, who's been providing Stan's voice, all day.
Lexie is upset to find other interns practicing insert IVs on each other, but when she realizes that the unclaimed cadavers in the morgue are often donated for students to learn on, she seizes the opportunity. "Bow to me, for I am the queen of the interns," she tells her jealous colleagues. "I have assembled an army of the dead to teach us." But Alex and Cristina overhear and insist on taking the cadavers for their own.
Richard wants Owen's input on who should be awarded the solo surgery. "You don't have any history, any relationship with anyone. That perspective is rare," he says. Owen asks Callie for her input and after she rattles off her complicated personal history with all the residents, he tells her he wanted to know about their medical skills.
Owen tells Richard he finds the residents, "Undisciplined and inarticulate. I'm not sure I want to stay."
When Miranda finds a room full of corpses that have been opened up, Lexie tries to explain that they were unclaimed and an outraged Miranda insists, "We claim them. We owe them respect."
Cristina is convinced that Owen hates her, especially after he chews her out for trading procedures with Alex on a badly beaten homeless man. Owen orders them to step away from the patient. "You have no decency, no respect!" he shouts. He tells Cristina that if she's practicing medicine just to win competitions, she has no place being here. In response, she 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. "This is why I'm' here," she says.
Earlier, Owen had overheard Derek telling Mark that Cristina was a "single malt scotch," but a frustrated Mark pronounced her a "bad wine." After Cristina leaves, an impressed Owen murmurs, "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. "My patient lost a heart over this. It is damn well going to be investigated." 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.