Derek is very upbeat about finalizing his divorce from Addison. He lets her have the Manhattan brownstone and their house in the Hamptons; he just wants to keep his trailer in Seattle. She tries to tell him it wasn't just a one night stand with Mark, but he's determined to be the bad guy since his adultery involved an actual relationship.
Izzie's happy too. She shows Meredith and George the $8.7 million check and promptly spills orange juice all over it! She talks about what she might do with the money maybe open a bed and breakfast. They anxiously urge her to deposit it in a bank, and she says she will, right after she cleans out her hospital locker. She later tells Addison she feels guilty about the money.
The interns are excited to be invited to an "M and M" (morbidity and mortality) session, an overview of how patients died and how such deaths can be prevented. Their enthusiasm dies completely when they realize the first patient being discussed is Denny Duquette. Burke is doing the presentation, but another doctor challenges his facts, saying it's common knowledge that an intern cut the patient's LVAD wire. He also wonders why Bailey isn't speaking, because she was the resident in charge.
She steps up to the podium, only to have the same doctor mention that because she's a new mother, surely her sleep deprivation and fluctuating hormones factored into the whole situation. She talks about how Dr. Burke had been shot and how much chaos the emergency room was in but he insists her interns have no respect for her authority, since they never answered her pages.
Izzie is standing in the back of the room and hears the whole thing. George offers to watch her all day, with the Chief's blessing. The interns try to apologize to Bailey, but she tells them they don't have that right.
A woman with breast cancer is having second thoughts about a mastectomy. Her husband appeals to Bailey to talk to her and offers to let her hold his child since she's the "baby whisperer" but with the doctor from the M and M in earshot, she coldly refers him to someone else.
Later, the Chief sees her brush off the patient's husband again and he tells her she's a better doctor because she's a mother, and not to stifle that part of herself. She goes and talks the patient into her mastectomy. And when the hostile doctor sees her with the patient's baby, she tells him to watch out because her hormones are up and she doesn't know what she might do.
The Chief tells Burke how glad he is to have him back because he's also such a great authority figure, and Burke doesn't have the heart to tell him about his shaky hand.
Izzie stops in to see Burke. She says she's fine but he knows better. He got shot. Denny is dead. Neither one of them is fine. He tells her not to feel guilty about Denny, but to feel guilty about not using her two good hands as a surgeon.
A middle aged couple comes into the ER in a very awkward predicament they got stuck together during sex! They explain they got divorced five years ago but keep meeting for sex. From the X ray, Addison determines that the man's genital piercing is caught on his ex wife's IUD. She directs Meredith and Cristina how to separate them, but during the procedure, the husband has a heart attack.
Burke is called into surgery and he and Cristina work out a code if his hand starts to get tired. During the surgery, he coughs and she asks if she can practice her running web stitch. The other interns are insanely jealous. Izzie goes to the Chief and says that she has all this money, but all she wants is to do a running web stitch.
The ex wife of the heart attack patient tries to explain her ongoing affair to Addison, saying she stopped feeling guilty about it after a while, but that "the truth has to come out" and that she's going to tell her new husband.
Taking this to heart, Addison runs into Derek. He comments on how wonderful it is that they're both being so civil. She confesses she lived with Mark for two months after he left and that they're both equally responsible for the end of the marriage. His smile fades and he says he never wants to see her again.
Mark finds Derek and says he's glad he knows the truth now and how Derek must feel like he wasted a year of his life trying to be with Addison when he really wanted to be with Meredith. He tells him, "as a friend," and Derek replies, "You're not my friend."
Meredith keeps running into Derek, but can't bring herself to tell him she broke up with Finn. When they end up in the elevator again, she tells him, but her timing couldn't be worse. It's right after Addison dropped her bombshell so Derek just says, "Okay," and walks away.
Not realizing Callie's broken up with him, George shows up to her hotel with snacks and movies, but she slams the door in his face.