Callie and Arizona still have a “Grey’s Anatomy” storyline that focuses on their moving in together — this week it’s that they want Owen and Cristina to move out and don’t feel like they are taking steps towards this fast enough. Meredith is the one who has to point out to Callie that Cristina can’t even sleep if Owen is gone (she goes to Meredith’s and crawls into bed with her… and Derek… so that she can finally get some sleep) so Callie then thinks they are monsters for wishing the couple out. It turns out, however, that all she and Arizona needed to do all along was come home and start ripping each other’s clothes off right in front of Owen and Cristina before moving into the bedroom for drunken sex, and that gets the newlyweds thinking about their own place right quick.
Cristina is still doing terribly — during a meeting the attendings all argue about what might be best for her, and most of them think she needs to be moved to administration or something similar for a while. Derek, though, stands up for her on account of her saving his life and puts her on his service, figuring administration is the last thing that would be good for her. It doesn’t do a ton of good, though, because Cristina is flippant and sullen and can’t bring herself to even answer questions about how they might treat a patient, much less actually help with anything in surgery. Derek finally talks to her and tells her that she’s got the most potential of almost anyone he’s ever seen, but she finally admits that she doesn’t even remember his surgery, except for bits that sneak up on her like in the OR last week, and that she just wants to be left alone. He decides to take a step back, and instead helps her through reenacting his surgery on a corpse, but it obviously doesn’t do what Derek wishes it would, as she admits to Owen later that she might be happy being a plumber instead.
Derek has quite a day overall — in addition to the difficult task of trying to help Cristina, his little sister Amy shows up at the hospital because he’s been ignoring her calls ever since he was shot. She brings him a “gift” in the form of a guy with a brain tumor, and he figures out that she met the guy while having a mile-high tryst on the way to Seattle. Amy is also a neurosurgeon, but she seems like a loose cannon and Derek wants nothing to do with her, so he tries to keep her out of the OR and away from him, though fairly unsuccessfully. Mere doesn’t get why he seems to hate her until he explains that Amy totaled his car while high on drugs that she obtained by stealing his prescription pad. It turns out that she’s always acted out due to her own trauma of being there with Derek when their father was shot and killed, and that all she’s really ever wanted to do is actually talk about it with him. When he finally opens up about it, they have a Moment and seem to get back on the right track with each other.
Lexie, Bailey and Mark get a patient whose entire body is covered in warts — to the extent that his hands look like grotesque gray-green claws and his face looks like he’s wearing a fright mask. Lexie flips out when she first sees him and so Bailey makes her work closely on him all day as penance. Lexie feels a little bit better, though, when a spider crawls out of one of the growths during surgery and Bailey starts dancing around and screaming like a little girl, proving that everyone has something about which they can’t always stay totally cool. Lexie also still thinks that Mark thinks she is a freak, but in a drunken moment April finally tells her that Mark clearly is still in love with her. Lexie looks rather pleased with this idea, but when she goes to find him, he’s about to embark on a couple of quality hours in the on-call room with none other than Amy.
And finally, everyone faces up to some hard truths that they’d all rather not talk about, for instance: April is a virgin, Alex is afraid of the elevator, and Teddy has a pattern of only picking unavailable men. While the Chief helps Alex by riding in the elevator with him until he is bored rather than scared, April and Teddy are still on their own for now.