Bailey presents Arizona and Mark with the attendings' recommendation that they deliver the baby now, prematurely, in order to give Callie the best chance at survival. This leads to a huge, bitter argument between Arizona and Mark about what Callie would want -- Arizona says Callie would want the baby to live no matter what, while Mark thinks it's insane and that Callie won't be able to want anything if she's dead. In the midst of this, Bailey may have an idea.
Original Artist: Get Set Go
Performed by: Bailey, with Kepner and Lexie
Most Portentous Lyric: "And you will wait too long / he will be gone"
I guess this is just Bailey's fretting anthem as she looks over Callie while Arizona and Mark scream at each other. Meanwhile, Avery finds Lexie and updates her on the plan: surgery tomorrow, with the question being whether they deliver the baby first, subject to Mark and Arizona's argument. Lexie asks how "they" are doing, which Avery correctly interprets as her asking after Mark. He seems to take it in stride and understand why she's worked up for Mark's sake, but when he asks whether she wants to come home or stay the night at the hospital, and she intimates that she's staying because Mark might need her, he kind of stomps off. Tough position to put Avery in, but I'm leaning towards telling his pretty face what Alex told Lucy: "Suck it up."
Elsewhere, Derek and Meredith are in the on-call room, with Derek kind of a mess over the fact that, try as he might, he may not have prevented Callie from getting permanent brain damage. "She might not ever come back," he says.
Back to Arizona, who's ticking off the laundry list of problems for babies born this premature and accusing Mark of not caring about the baby. Mark thinks that's pretty rich since A) it's his baby, and B) Arizona never wanted it in the first place. She screams back that what she never wanted was HIM in her and Callie's lives and that he's basically a sperm donor. He fires back that she doesn't get a say as she's not a biological parent. "You're not anything," he spits. "You're nothing!"
All the while, Cristina has been obsessing over Callie's heart scans, and finally, she stops. She gets an idea. "Wait!" she song-titles, then sends us into the commercial break all aflutter.
After the break, we're inside Callie's reverie, as she's imagining a sliiiightly altered version of her fateful car ride with Arizona. They're still arguing about Mark, although a few of the details have changed -- like Arizona tells Callie to go ahead and answer the phone when Mark calls. Oh, and their car is flying through the sky at sunset. That's also different. Suddenly, Callie realizes that Arizona's about to ask her to marry her, "and then we're gonna get hit by a truck." Arizona's like, "No, I'm not. But also, put on your seat belt." Callie starts blabbering about whether she'll say yes, if that's what love is like, for everybody else on the show who's paired up. Arizona's like, "Wonderful -- seatbelt!" But no, Callie would rather sing.