The next morning, Cuddy wants to know why the doctors' lounge is covered in mud. House smoothly explains that CTB and 13 had an argument and the cafeteria was out of Jell-O, even though there is always room for it. Cuddy's not buying that, since she also saw the pickaxes the Numbers stupidly left there. Based on the mud and the tools, Cuddy guesses that either House made his fellows dig up a corpse, or they're building a railroad. When House tells Cuddy they're looking for Mad Cow disease, she's totally fine with the grave-desecrating and tells House to tell her when he gets the results. She asks House how many of the Numbers agreed to dig up a grave, and he proudly answers six out of seven. And no one objected for moral reasons. Hooray!
House walks into the lab, where the Numbers are busily testing old-dead-guy brains. He hands PS a mop and orders him to clean up the doctors' lounge, even though you know it was Kumar who left the place a mess. PS complains, but obeys. The Random Guy says the tests came back negative for Mad Cow disease, which means they did all that digging for nothing, except to give House the valuable information that they will do anything to keep their jobs. House says they'll have to start over again.
Cole and the ladies report to Irene's room to collect blood and stuff. Irene just wants to leave, saying she's probably fine now, as seizures and rape hallucinations are the kind of things that normally resolve themselves. The old foreign lady is still around, and she worries that Irene won't be able to drive herself home, to which Irene says the lady can drive her. At this, the Numbers ask Irene who she's talking to. "My mother," she responds. And then we realize that while Irene and the viewers can see the woman, nobody else can. She's the Ukrainian Bruce Willis!
Back in the classroom, House is kind of annoyed at the Numbers for going through all that grave-robbing trouble and not even noticing that their patient was totally hallucinating. Whatever. I want her illness. I want to hallucinate up my mother when I'm sick and have her sitting by my bed comforting me. Or maybe not, since it turns out that Irene's mother is dead, and has been for the last twenty years. PS says that Irene didn't mention having hallucinations. Well, duh. She doesn't know they aren't real, so why would she report it? The Other Guy reports that all the labs came back fine. Weird Beard proves his worth by saying that while seeing your dead mother is a hallucination, the fact that Irene doesn't realize her mother is dead is a delusion. An old-guy war starts to brew as PS says that carbon monoxide could cause the delusions and Weird Beard counters that Irene has no symptoms of that, and PS's medical school clearly didn't teach him very well. Whereas Weird Beard's medical school is either a hallucination or a delusion.