We finally get some levity this week -- well, as much levity as you can get when you're working with one doctor trying to come to grips with her widowhood, two doctors whose marriage is in crisis, and an intern with a desperately ill preemie and an ill-advised crush on her resident.

As Mere and Derek drive to work one morning, they look out their window to see a lion nonchalantly crossing the street in front of them. They get to the hospital just ahead of two patients who have been mauled by said lion and come to find out that one of those patients was actually the lion's owner, keeping him as a housecat. Just in case anyone was curious, keeping a lion as a pet is in fact a Very Bad Idea. Jonathan from Buffy is one of the maulees; he had gone to the woman's house to pick her up for a date and wound up having his appendages ripped to shreds. Richard and Avery sort of fight over who gets to have the fun of treating him and wind up working together and bonding, weirdly, over the awesomeness of finding one of the lion's teeth in his body during surgery and the fact that idiot patients provide awesome(ly creepy) medial souvenirs.

Cristina is still not speaking to Owen, a week after his Great Affair Reveal. He now finally wants to talk, which she had been begging him to do for weeks, but she's no longer interested. She spends the day trying to build hearts from scratch -- which is obviously super painful because it's a cringingly literal metaphor for what she wants to do in her personal life. Meredith is working with Owen that day and in his desperation, he begs Meredith to put in a good word and tell Cristina how sorry he is. She wants to not talk about it but he keeps trying and finally, in front of Bailey as they all work on the lion owner, he blurts that it was just sex. It's extra awkward because until that moment, Mere didn't actually know about the affair.

When he tries to talk to her after surgery she repeats for the umpteenth time that she doesn't want to talk about it and informs him that Cristina not telling her about it means that Cristina doesn't want Mere to hate him, which then means that she must eventually be planning to forgive him. This finally puts a stop to Owen's begging Mere to be a go-between but he's another embarrassing situation because now Bailey knows about his big mistake as well. He talks to her later and offers to steer clear of her since he knows that Cristina is special to her, but Bailey tells him that while he did something terrible, it doesn't make him a terrible person. He seems to find a little bit of comfort in all of this and when he gets home, sits down at the table across from his wife to eat some dinner. After a moment, however, she jumps up and throws her bowl of cereal in his face, thereby assuring him that she's not actually anywhere close to forgiving him.

On the other end of the relationship spectrum we have Mark, who is starting to think about asking Julia to move in with him. Lexie overhears this and then tries to tell Derek that it's a horrible idea, but Derek refuses to have a personal conversation like that with her. After a while, though, he changes his mind and tells Lexie that he's not going to give Mark any advice one way or the other but he knows that Mark is going to do it unless he thinks he has an actual chance of rekindling things with Lexie. Derek warns her that if she says anything, she'd better be sure that she really wants to get back together with him and isn't saying something just because she's jealous and hates seeing Mark with someone else.

Callie is dealing with some jealousy of her own when she sees a nurse give Arizona a lingering hug goodbye and realizes that they once had a fling. Arizona tries to brush off the subject but Callie hammers away at her, trying to find out just how many exes she has in the hospital. Finally, exasperated, Arizona starts listing her rather impressive list of conquests, which sends Callie into a tizzy despite the fact that Arizona already knows about all of Callie's own exes who still roam the halls of their workplace. Mark finally pulls Callie aside and points out that Arizona is faced with Callie's past every single day since she's helping raise the daughter her wife drunkenly conceived with her friend. But, she has gotten past the jealousy and Callie now needs to suck it up and do the same. She does, and shows Arizona just how over it she is while peeling both of their clothes off at home that night.

Teddy is also dealing with her own demons in the hospital when she treats an elderly patient who was about to go on an anniversary cruise with his wife. He and his wife are super in love and cute, and the wife is terrified at the idea that she might actually lose her husband during surgery. Teddy is rather touched by their relationship; she has been doing a great job of shoving down and ignoring her own grief but seeing the two lovebirds is starting to cause some cracks in her defenses. The husband almost dies during surgery but she and Alex manage to get him all fixed up, and she happily goes to tell the wife about how well it went. She gets to the waiting area and sees that the woman has fallen asleep in one of the chairs but as she sits down and tries to wake her up, Teddy realizes that she has died. When Teddy has to tell her patient she breaks down upon seeing his raw grief, but it does seem like it might be what she needs to start getting through her own.

Alex, meanwhile, had been working with her because he couldn't handle being around Morgan any longer. While it seems like deep down he might have some feelings in his small dark heart for her, he can't handle her adoration and asks Arizona to be taken off of baby Tommy's case. Morgan spends the day texting him, demanding to talk to him, but he avoids her at every turn. While he's gone, Arizona and April tell Morgan that Tommy needs another surgery but that things are looking really bleak for him by this point, and she might want to start considering AND: allowing natural death. She's horrified by the idea that her baby might not make it and is desperate for Alex's help in making her decision. But when she finally corners him, he yells at her that this is a decision she has to make on her own, especially since he is neither her boyfriend nor the baby's father. She finally does make one (they're doing the surgery) but wants Alex nowhere near them anymore. Arizona tells him that he did the right thing and that his actions are actually going to force her to be a stronger mother, which is what Tommy needs, and Alex dutifully agrees that if hating him gives her the energy to be strong for her baby, that's great. But his dismissive reply seems to be covering up feelings he's trying to bury, as we have seen so many times before.