So, the "No Fraternization Rule" is in place, and the only couple it really impacts is Jo and Alex. They stage a big fake breakup in front of half of the hospital so that they can continue to sneak around and be all lovey-dovey. When they sneak off to do it in a supply closet, though, they run into April and Jackson who are having their own secret marriage sex, and then Richard walks in on all four of them. Alex figures this is no big deal and the board isn't really going to enforce the rule, but he finds out he's wrong when he's called into an emergency meeting for the four closet sex-havers to face the music. The board offers a pretty fair solution, which is that what the sex-havers do on their own time is their business, but they need to keep it professional at work. Imagine that?! But Alex is livid and won't stand for it, and yells that he's tired of sneaking around when all of these other married couples are all loved-up and obnoxious, and that they can fire him if they want but he refuses to comply. After he storms out, Jackson and April fess up that they are actually married and therefore not breaking any hospital policy. They spent the day treating a woman totally hung up on her married boyfriend and came to realize that they didn't want to hide their love away anymore anyway, so while it wasn't the way they wanted to announce it, it's ultimately a happy thing.
Before his meltdown, Alex, Callie and Bailey have a teenage patient with a gene that makes her susceptible to all sorts of cancers. Bailey does some research and realizes that the girl, her mom, and possibly her sister have an incredibly rare disease, and tasks the interns with finding the few existing case studies and trying to figure out a treatment. The residents are all at war with each other because Jo thinks Stephanie is the one who filed the complaints, everyone still seems to not trust Ben because he's older and married to Bailey, and Smash is just trying to get his work done and keep to himself. After Jo confronts Stephanie and lays into her for ruining her relationship, it comes out that Leah is the one who actually filed the complaints and that she did so because all this bullshit is compromising her education and obviously right now it's also happening to everyone else too. Smash finally speaks up and convinces everyone to focus on medicine and work together, and they come up with a possible treatment but not before the girl unexpectedly bleeds out in surgery. (The weak consolation is that their plan wouldn't have helped her since her aorta was basically shredded, so we aren't dealing with any sort of "if only we'd started working on this earlier, we would have been on time," nonsense.) Later, they then band together (minus Jo, who is still facing the board) to go drink and even invite Ben along.
Derek has to go to Washington for yet another interview, and Mere is still annoyed at the whole situation. She admits that as his wife she wants him to get the job, but as a surgeon who wants to do her own research she doesn't. However, she also realizes she has to hand her research off to a bioengineer so she couldn't continue on her own anyway, though admitting that to Derek feels like it would be letting him win. She invites Cristina over for a sleepover and the two drink wine and talk about Cristina and Owen -- she overheard him say that he and Emma are going to move in together and she realizes that would mean that they are really, truly, actually over since surely moving in would lead to kids and all that. She wants him to be happy, but it still makes her awfully sad. Derek then shows up because his interview was cancelled, so she orders a cab to take her… to Owen's trailer with a bottle of wine so she can congratulate him on this big step. Of course as they talk, they clearly realize how much they miss each other and totally wind up having sex. The next day, Emma talks to Owen about how many kids she wants and how she wants to take a few years off of work to raise them, and while he assures her he's not freaked out by the conversation, that combined with the cheating with his ex-wife makes him think. That night, he breaks up with Emma and tells her it's because he wants to be with someone passionate about surgery and talk about medicine every night instead of children. So I guess that actually makes one more couple that's going to be sneaking around in supply closets.
Oh, and the reason Derek's interview was cancelled? Is because they didn't need to grill him any more since they had already decided that they actually want him to head up the whole fancy Presidential study.
Sex, sex, sex. Jo and Alex are having it, and Emma and Owen are having it. But Emma and Owen take their bedroom talk up a notch when Emma teases Owen about living in a tin can and he responds by thinking for five seconds and then suggesting they think about moving in together. She thinks for five seconds herself, agrees, and happily mauls him with more kisses. There's no way this can go wrong! Just in case we didn't suspect that this might all go to crap, Mere VOs that cancer always sneaks up on you when your body is feeling particularly safe and healthy or it's making plans to move in with its girlfriend who doesn't have any sort of distinguishing personality traits.
Derek is choosing a tie for yet another presidential interview while Mere starts to get ready for the day and grouses that she wants Neurosurgeon Derek Shepherd to get the job but not Husband Derek. She goes to take a shower and he tries to get in on that action, so to speak, but she shuts the door in his face after reminding him that he went back on his promise, and she can't sleep with a lying liar who lies. She taunts him from behind the door but he doesn't actually seem too bothered by it, probably because he's too excited about his date with the President.
Mere is still going on about how cancer is the master of surprise. Callie is unpacking boxes and when Arizona comes to the room Callie forces her to open a box although Arizona is trying to get the family out the door for the day. Once she opens it she finds a tiny gift box, and honestly seems more terrified than happy as Callie urges her to open it. Inside is a beautiful sapphire ring, and Callie happily says that she had the band inscribed with the date they moved into the house, their "new start." Arizona still seems pretty shocked and tentative but does whisper Callie's whole name, so I guess she does actually like it? I don't know if this is a sign of things to come or a weird acting choice. Regardless, Callie is super excited and urges Arizona to put it on.
Meanwhile, at the hospital, April hisses at her secret husband to take his ring off, since he clearly forgot. They have a horrible fake conversation to try and cover their tracks but no one is paying any attention since everyone is gathering at the stairs for an announcement from Owen. As Owen and Derek walk up, they talk about his and Emma's moving in together, and Cristina totally overhears and reports this development sadly to Meredith. There's no time to discuss because Owen calls them all to attention to announce the new "Non-Fraternization Policy." For the first time in the history of the hospital they realized that they are supposed to be a safe work environment and focus on patient care, which surely isn't going to stick because that sounds like the most boring television drama in the world. Yet also, this is approximately ten seasons overdue. The policy states that relationships between co-workers will be discouraged, while those between superiors and subordinates are forbidden. Jo's chest heaves when they announce this. Owen then tells them that their supervisors will arrange meetings to go over the actual details.