The central case on this episode of Grey's Anatomy belongs to Hahn. Mike is suffering from the same heart condition that Denny suffered from, narrowly missing out on a transplant a couple of years back.

It dawns on Izzie: he's the guy who was supposed to get the heart she stole.

They're going to do a procedure that will buy him some time until he can get another transplant, injecting ethanol directly into his heart, to destroy damaged tissue and help with his breathing. He has to be awake for it.

This case really begins to haunt Izzie - the guy's in Denny's old room, and she begins to see Denny walking the halls. In surgery, she freezes, seeing Denny, and bolts from the OR.

Meredith explains to Hahn the history of Denny. Hahn then goes to Callie, who fills her in on Izzie's relationship with Denny, the LVAD wire, the suspension, and what it cost Izzie. Hahn demands Richard fire Stevens ASAP and an ethics investigation be launched but Richard shuts her down.

Izzie's guilt is killing her. She hides from Hahn and everyone else, but when she goes to face the music and talk to the guy, Hahn insists she be there for the a second procedure.

Izzie keeps seeing visions of Denny, but during the next procedure on Mike, she eventually pulls it together enough to help him get through it.

There Denny is again. This time, in the locker room, she talks to him and begs him to go away because she's over him. But he comes back, a reminder that she hasn't moved on.

As for Erica, she tells Callie she intends to report the Denny-Mike case to UNOS, costing the hospital its transplant certification. Callie has no love for Izzie, but thinks the situation was handled appropriately.

Callie says actually she can, and Erica, appalled, walks away saying she doesn't know Callie at all. She will not return.

Elsewhere, a woman named Rosie comes to see to Derek and Bailey. She has a brain tumor, the type of which is prone to bleeding. She signs a Do Not Resuscitate order. She and her husband bid farewell as they always do when she goes in for a surgery, before they say hello again when she wakes up.

Derek and Bailey marvel at the couple's closeness and the strength of their bond - Bailey's in marriage counseling as we speak.

The surgery doesn't go well.

The tumor bleeds, and Rosie doesn't regain consciousness. Ed, her husband, at first doesn't understand why no one's moving to help her - and then the impact of the DNR sets in. It's a moving scene as he tries to resuscitate his own wife and the doctors must try to gently convince him she's gone.

A trauma comes in - a man beaten to the point of unrecognizability - and the Chief asks Hunt for input on the residents he's sizing up for a major solo surgery. While he watches Cristina efficiently handle the trauma, Hunt is horrified with the way she bosses around Lexie and shows no compassion.

Owen says he is astonished and dismayed that Cristina is planning for this guy's death while he's trying to save him.

In fact, the attitude among Cristina, Karev, and Lexie is all focused on procedure and the competition, which appalls Hunt.

Later he tells the Chief that his residents are undisciplined, inarticulate, and more interested in their personal lives than anything else.

In the end, Cristina finds an upset Hunt and tells him that the patient's wife identified him. Then she talks about how being in the car accident at age nine - her father was killed - has affected her and shaped her as a surgeon. And the patient's name is Tom. Hunt looks at her with more than a little respect and admiration, rather than disdain this time.

Richard introduces the staff to Stan, a robot patient simulator, which does battle with George. On her trip to the morgue, Lexie lays claim to several unclaimed bodies to use for practice - which the interns and our residents readily embrace. Later, Bailey finds this and demands they treat the people with respect - living or dead, they are humans.

As for Meredith and Derek, he's not getting a ton of sleep because as they devour her mother's journals because Cristina keeps calling Meredith in the middle of the night to talk about them for some reason. Surgical junkies.

Derek becomes convinced that Cristina needs a distraction, and convinces Mark to try to sleep with her. Sloan commences to hit on Cristina but his advances all sail over her head. Later, Meredith and Cristina give Derek a hard time for this, and they all laugh about it.

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