And so, they camp out in the kitchen (which is STILL full of unpacked boxes, like, haven't they lived there for months now? Come on, guys) behind the island and wait for the mystery prankster to show up under the cover of darkness. They're armed with a flashlight (Wilson) and a cricket bat (House). Because House can't unpack his dishes but he made damn sure his cricket bat was easily accessible. Wilson starts to wonder if this is all part of a prank on House's part to trick him into staying up all night waiting for something that will never happen. Perhaps he was the one who loosened his own tub rail to make it more convincing. A "self-prank," as Wilson describes it. "I don't master-prank," House says. Wilson doesn't believe him, though, and retires to his bedroom -- just as the fire alarm goes off and the sprinklers start spraying all over the apartment. Wilson runs back into the kitchen screaming about "the flat screen!" which he tries to save from the water with, like, two dish towels. Yeah, that's not going to work. Why is the TV so close to their kitchen anyway? And why does their sprinkler system go off as soon as the fire alarm? What if they simply set it off by accident while cooking some bacon, like I always do? This seems like a serious design flaw. Wilson decides that House is innocent of the pranks, as he'd never do something to their precious TV. "This guy is good," House says admiringly.

The next morning, the Cottages, Marcus and Cuddy have been called into the meeting room. As Cuddy wonders aloud what's going on, House enters with a French accent and accusations, figuring the perpetrator of the condo pranks is in the room as everyone there had both "motive and opportunity." I think it's 3B. She's probably still mad at Wilson and House and we know she has the necessary flat-head screwdriver. Cuddy, meanwhile, stupidly believed that the emergency House paged her here for was an actual emergency. She will never learn. "Not zo fast, Mademoiselle Cuddy! No one leaves here until zhey can account for zheir whereabouts zhe evening last." No one except Cuddy, who totally leaves without accounting for her whereabouts the evening last. House switches back to his American accent and reminds the rest of the room that he's their boss and thus they don't have the same freedom to leave. He abandons the French detective for a Clue theme. "Professor Chase," who House says has the motive of blaming House for his marriage falling apart, says he was at PPTH all night with Hadley as they treated the patient no one cares about. "Colonel Taub" was having dinner with his wife. "Really?" House asks. "Yes. Really," Taub says. House decides that's good enough because the real focus of his investigation is Foreman, who denies his involvement by saying he doesn't even know House's address. House says he can't believe that, since he now knows that Foreman is a liar "by omission." Uh oh. Marcus knows where this is going, and lets out an angry warning "House! Don't." But of course, he does. He tells everyone that Foreman's mother died, which comes to a surprise to them all. Wilson pipes up that this might not be the appropriate time for any of this. Foreman admits that his mother died three months ago. Weren't Hadley and Foreman still dating then? I guess not. "I'm so sorry," she says, sounding sincere. "Why didn't you tell anybody?" Taub asks, because that's important now. I know that when I want to express sympathy to a friend or co-worker who has lost someone, the first thing I do is buy them a card that says, "why didn't you tell me?" on it. House adds that Foreman "refused to say anything nice about her at the funeral." Well, that's not exactly true. Marcus just said he "heard" that Foreman didn't give a eulogy. Foreman says he didn't think it was anyone else's business. About ten minutes too late, Marcus jumps up and tells House to stop and that Foreman doesn't owe his boss any explanations. House tries to goad Marcus into hitting him, thus forcing Foreman to show how much he cares by telling his brother to calm down. Marcus dramatically quits his job (which didn't really exist in the first place anyway) and leaves. Hadley urges Foreman to stop Marcus because "he needs this job." Foreman decides that 77 needs a new IV more.