It appears that Callie is in a hotel room (her old apartment is being sublet), living in depression and squalor. She jumps at the ringing phone, only to be bummed when it's Mark, asking what she knows about Cristina. From the looks of the "She WHAT?" reaction, it's safe to say she hadn't heard.
Altman and Hunt emerge from the auditorium bitching about Derek's attitude. She asks him how Cristina's doing, and he says she's fine and acting totally normal, except any time he brings up work, she goes blank and ignores him. He thinks she just needs time. Richard comes up to Altman and says there's an emergent patient being admitted and to meet him in the V.I.P. wing. ...Seattle Grace has a V.I.P. wing? Is that for when, like, Ichiro or the Starbucks mermaid gets sick? Richard then tells both doctors that he's required to send a letter to the American Board of Surgery informing them of Cristina's resignation. Is there any reason for him to hold off on sending that letter? They both quickly say "Yes," and ask for just a little more time to work on her.
Avery, Kepner, and Lexie are going over charts, with Avery continuing to fret about the attending not wanting him. He decides he hasn't screwed up with Bailey, he'll ask her. He asks Kepner whose service she's on today, and she replies "Karev," then corrects herself to say Dr. Stark, the new pediatric surgeon she'll be shadowing with Karev. Avery and Lexie click to the Freudian slip pretty quickly, though, and tell her not to go there. "Trust me," says Lexie. "And don't be paranoid," she tells Avery as she walks away, "trust me on that too." Avery gets a look at Lexie as she departs, which Kepner calls him on with a "don't go there" of her own. "I'm a guy," Avery says, "I live there." Stop making my doctor boyfriend say stupid things, Shonda, damn.
Callie drops in on Cristina, who is dancing around, listening to her headphones, pretty clearly ignoring the outside world. Callie gets her to take the headphones off long enough to say that Mark told her that she quit. At the first mention of work, Cristina's got the headphones on and is bad to dancing. Callie gets her to stop again, so an exasperated Cristina explains that she had started to unpack but then got sick of it, so she stopped. She notes that Callie just got dumped for Africa and has a week before she's due back at work. "You're completely free, the world is your oyster, make lemonade!" Cristina starts bouncing off some walls as Callie muses that she was going to get a haircut and make a radical change, but then she thought that was maybe not the best idea. Cristina grabs a pair of scissors and cuts a giant hunk of Callie's hair. Callie screams, but Cristina, crazed look in her eyes, says, "Let's make lemonade!" Now both women are laughing maniacally, so it's clearly catching.