Taub and Chase run into Sir William's room, where Hadley is standing around a bunch of beeping machines. She says his heart rate is slowing, but doesn't seem to want to do anything about it. Instead, she notices that Taub and Chase aren't wearing their anti-MRSA suits and asks what's up, because that's the most important thing right now. Taub quickly tells her it isn't MRSA as Chase runs up with a syringe of epinephrine. Taub advises against that, saying it could "blow [Sir William's] heart out." Chase does it anyway. Oh, and then Sir William's heart stops. "I told you!" Taub says, because now is definitely the time to lord your personal victories over your co-worker. Especially since one second later, Sir William's heart rate is back and normal. "And I told you," Chase says.
So now that Sir William has a heart problem, poison ivy is no longer a credible diagnosis, nor is an epinephrine allergy. Chase suggests an infection caused by a usually harmless bacteria taking advantage of Sir William's weakened immune system. But House doesn't like any of their choices for what could have caused Sir William to have a weakened immune system, so he goes back to his environmental thing. Hadley insists that they tested all of the food stands at the fair and they were (shockingly) clean. "Maybe he got the poison somewhere else. Or maybe you just missed it," House says. He orders them to treat Sir William for trichinosis, then do a muscle biopsy to test for it.
House finds Wilson in the main lobby, and Wilson reluctantly invites him out to dinner with him and Sam, saying Sam wants to get to know House better and thinks Wilson was trying to hide his roommate from her. Which he was. And was wise to. But he doesn't want her to know that, so he's forced to take House out to dinner. Very stupid, Wilson. I would have just told Sam I was hiding him from her. Once House ascertains that Wilson is "asking [him] to condone a relationship based on lies and mistrust," he only wants to know "when and where?" Wilson says it's tonight, which is really short notice, especially since House doesn't know what to wear since "all of [his] cereal boxes are at the cleaners." Wilson tries to level with House, saying that while he appreciates him trying to look out for him, he doesn't need or want his help. "Come to dinner and be your usual selfish self," Wilson asks. He can't possibly think that's the best way to phrase that, right?
Shannon tells Sir William that King Miles promised to "stop by later." Wow, King Miles does not give a shit. Sir William says he'd rather King Miles not come at all because he doesn't want him to see his knight sick like this. Shannon asks if she should leave too, then, and Sir William says no a bit too quickly. Of course, Hadley's there to butt in. "I think he's saying it's different with you, Shannon," she says, much to Sir William's horror. "Uh, it's a guy thing. They don't like showing weakness in front of each other," she adds. Way to dig yourself out of the hole you just created, Hadley! With that, she asks Shannon to wait outside while she collects some biopsy material. "Don't hurt him," Shannon asks. "He's safe with me," Hadley assures her. Yeah, but his secrets clearly aren't. As soon as Shannon leaves, Hadley urges Sir William to tell Shannon how he truly feels, thinking that Shannon has feelings for him, too. Oh, mind your own business, Hadley. Don't you hate love? Sir William says knights are supposed to be selfless. Hadley reminds him that while that might be true in theory, it's never been true in practice. "If you want to be king, sometimes you have to be willing to take what's yours," she says. Methinks Hadley watches a little too much of The Tudors. "She's not mine," Sir William says. "She's not his either. Not yet," Hadley says. Ah yes, weren't the medieval times when women were thought of as chattel just the greatest?