Meredith tells Derek she's not into church weddings or "poofy white dresses," but it's out of her hands: Izzie has declared herself their wedding planner and arranges for several wedding dresses to be delivered to her hospital room. Meredith is worried that Izzie's enthusiasm will result in "bridesmaids in pink taffeta and someone singing 'Wind Beneath My Friggin' Wings.'" Derek tells her it's worse than that. "We have to make time for ballroom dancing lessons."
Even her first chemo treatment doesn't slow Izzie down as she forces Meredith to try on dress after dress. Dr. Swender, the cancer specialist, is concerned that Izzie is going to wear herself out, maybe even give herself a heart attack. "A few hours from now, Izzie Stevens is going to wish she were dead," she tells Richard.
Owen begins therapy with Dr. Wyatt. He denies that the choking incident with Cristina is rooted in what happened with his platoon in Iraq.
Callie's father is in town for one day, so Callie doesn't plan to introduce him to Arizona as they've only just started dating. But Callie is forced to tell him she's seeing someone new when her father threatens to kill George for having cheated on his daughter. "Daddy, please be okay with this," she says as she brings Arizona over to introduce her. She tells her dad that the relationship with Arizona "just happened," but that she's happy. Her father's response is to announce he's taking her back to live with him and her mother!
Callie doesn't even consider saying no to her father. "He's done everything for me," she tells Mark, explaining how her father paid for college, med school and set up a huge trust fund for her. "He's supported me my whole life," she says. "Supporting someone and respecting someone isn't the same thing," Mark tells her.
Arizona urges Miranda to go home after working a 90-hour week and Miranda confesses that she hasn't told her husband about starting her pediatrics fellowship.
Izzie is still feeling great, until she suddenly starts vomiting. She gets out of bed to get a dress that's fallen to the floor and when she bends down, she collapses. She finally realizes that she's really sick.
At Lexie's request, Meredith orders Mark and Derek to apologize to each other before they begin a six-hour surgery together. Derek refuses and says that Richard, not Mark, is his choice for best man. He advises Meredith, who is upset at the news, to get over her grudge against Richard. "Don't talk to me about grudges," she snaps. "I'll get over mine when you get over yours."
Owen thinks that a man who was hit by a car was trying to commit suicide, so he's furious with Alex when he leaves the patient alone. The patient has disappeared and as Alex and George search for him they get into a shouting match over how much they hate each other. Outside, they look up just in time to see their missing patient leap from a window to land on a parked car below. The man is in bad shape, but still alive, as Owen rushes him into surgery. George assists and Owen is so impressed with his coolness under pressure, he tells George he should choose trauma as his specialty.
Mark and Derek bicker during their joint surgery. "I am done," Mark finally declares. "If I hadn't fallen for Little Grey, you would have found some other way not to respect me. You always have." But to Mark's surprise, after the surgery, Derek tells the patient's wife that it was Mark's skill that saved her husband today.
Mr. Torres offers to make a sizable donation to Seattle Grace to compensate for taking Callie back to Miami with him. Richard points out, "Your daughter is a grown woman." Torres tells him that she's still his child and that he still needs to protect her, even from herself. Callie finally confronts her father and he gives her an ultimatum: if she doesn't move home, he'll cut off her trust fund. "I cut him off," she dazedly tells Arizona.
A distraught single father with a terminally ill daughter won't admit that his little girl is dying. As Miranda comforts his daughter, he tries to arrange for a flight to Mexico where he hopes to find a miracle cure. "She needs her daddy for this part," Miranda tells him, saying he -- not her -- needs to be the last one to hold his daughter before she dies and he finally goes to his daughter's bedside to be there for her last moments.
Miranda is discouraged that she spent the day just holding a child instead of learning any kind of procedure. "What you did today is heroic," Arizona tells her and urges Miranda to tell her husband that.
Owen, comparing himself to his suicidal patient, can't forgive himself for wrecking Cristina's life the way his patient caused permanent damage to the man who hit him.
Alex joins George at Joe's bar and tells him, "You kicked my ass today. I'm good, but I'm not like you." He changes the conversation to Izzie. "She's really sick and I'm not good under pressure." George buys him a beer.
Lexie is sad that she won't be in the wedding since Mark and Derek haven't made up. "You're my sister, you're in the wedding," Meredith tells her, just as Mark and Derek come in together, grab a few beers and catch the rest of the game on TV, just like nothing ever happened between them.