Taub and Eva spend some time discussing Jack and how his "job" as the bassist of a band that is still looking for its big break 16 years on. That's why he's away from his wife and daughter all the time, which Eva doesn't like but apparently has to deal with because she loves him "so much." Taub tells her to stick with him because, assuming that his life-saving stunt wasn't because of a brain problem, Jack is a pretty great guy. I'm sure Taub thinks he's a pretty great guy too, but that doesn't seem to stop him from cheating on his wife all the time.
Boring! Let's see what Foreman and Chase are up to instead. While they look at things under a microscope, Chase wonders why Taub was picked to be the face of PPTH over Chase. Foreman knows why: Chase is a "pretty boy," and that's not what people want to see on an ad for a hospital. Which is absolutely correct; I probably wouldn't want to go to a hospital with a 12-year-old doctor. Foreman says his face wasn't used in the ad because he's black and the Princeton area is 80% white. Oh, please. If anything, Foreman being black would work in his favor with the marketing team, which always seems eager to show off a diverse workforce. But the PPTH marketing team is probably just as competent as its HR department or the security force, so there you go. Anyway, the tests come back normal, which means Jack is going to have his pituitary biopsied. While Chase sticks a needle up Jack's nose, he says he thinks they didn't use Foreman's picture because he always looks really angry, not because of the color of his skin. Foreman looks really angry but ignores him, and then Jack stops breathing and gives them something more important to worry about. Chase ends up sucking a "mucus plug" out of Jack's lungs to get him breathing again. That sounds disgusting. It also rules out both House and Martha M. Masters' theories.
Back in the meeting room, Martha M. Masters cheerfully reports that brain involvement has definitely been ruled out and they can now focus on other diagnoses that involve the heart and the lungs. House would rather not, as his new theory is that Jack didn't jump on the tracks to save a stranger, but someone he already knew -- he was having an affair with the woman, Chloe, and her seizure was not caused by epilepsy as they all assumed, but by the same thing Jack has. Martha M. Masters would rather take a culture of Jack's sputum (ew) and look for an infection, but House decides the lack of white blood cell count elevation rules that out and it also doesn't fit in with his Jack-is-not-a-real-hero-because-those-don't-exist theory. Some kind of toxin in Chloe's apartment, however, does.
Chase and Taub break into poor Chloe's apartment, as if she hasn't had enough to deal with lately, and Taub immediately complains about how ridiculous this is. Chase assumes Taub's crankiness is due to another fight with Mrs. Taub, but Taub says that, on the contrary, they've been having lots of sex lately. Which actually bums Taub out because Mrs. Taub hasn't been this horny in years and he's starting to suspect that Phil is who she really wants to have sex with, but since he's not there and Taub is, she's settling for him instead. Chase, whose marriage ended after like three months in divorce, doesn't see the problem in any of this. And while he finds a CD from Jack's band that proves he and Chloe had a relationship after all, Taub finds a can of roach spray that could be the toxin that made them both sick.
House does Clinic duty. His latest patient is none other than Murphy Brown, although he doesn't seem very impressed by her or her complaint of feeling tired and having pain in her shoulder when it's cold, especially since all of her tests say that she's perfectly healthy. House is typically short with and condescending to her, causing her to ask why doctors always seem to think they are so much better than everyone else. House thinks it has something to do with how they save people from dying and stuff. Murphy Brown keeps talking, saying that her daughter is a doctor and acts the same way, always dismissing her mother's concerns. "She sounds smart," House says, still not knowing where this is going. Murphy Brown waits for him to almost reach the door before dropping the bomb: House is "shtupping" her daughter. Because Murphy Brown is totally Cuddy's mom! Hooray! A rather shell-shocked House makes his way towards Cuddy's office, but she isn't there. He leaves a message on her phone instead: "we have a situation."
Chase and Taub confront Jack over their new theory that he's suffering from toxic exposure to the roach spray in Chloe's apartment. "Who's Chloe?" Jack asks. Taub and Chase aren't buying it, and then Chloe herself appears, lead to Jack's room by Martha M. Masters. It's obvious that Chloe and Jack are not having an affair and never met before the train incident, as Chloe tearfully thanks him for saving her life and calls him her "guardian angel," saying that one of her nurses gave her one of Jack's band's CDs when she was held overnight at another, much better, hospital for observation. While Chase and Taub are forced to look ashamed of themselves for thinking the worst of Jack, Martha produces a cup to take a sputum culture from him, smugly saying that with the toxic exposure theory ruled out (apparently Jack couldn't have been exposed to toxins unless it was in Chloe's apartment?), her infection diagnosis is looking better and better. Jack is unable to cough anything up for her, so Martha M. Masters pats him on the back to try to loosen something up. This causes Jack to lunge forward and scream in pain, holding his head. Um, why are we even letting Martha M. Masters near patients? She's almost as bad as the MRI (OF DOOOM!!). Jack is able to stop moaning long enough to tell the doctors that it's not his head that hurts, but his ears.
House reads the latest Subway Hero article in the New York Press (which I believe means that this did happen in New York and therefore Jack was ambulanced to PPTH's ER for some reason) before showing off the back of the paper and another PPTH ad featuring Taub. Martha M. Masters is pleased to ask House to admit that he was wrong about Jack, but while House will admit that Jack doesn't have a brain problem or a prior relationship with Chloe, he still won't call him a hero because jumping on train tracks is stupid. Martha M. Masters thinks that Jack's new ear pain symptom proves her infection theory and that the infection must have spread to his ears. Like, in one second. Because that happens. House says they can confirm that in a week when Martha M. Master's "secret cultures" have grown to testable levels. "Am I in trouble?" Martha M. Masters immediately asks, of course. House says she is not, because by taking those cultures she wasted her time and not his. He then decides on a diagnosis of acoustic neuroma, which sounds like some kind of nasty ear cancer, and Foreman says this somehow also explains the heart and lung involvement. While Chase, Foreman, and Martha M. Masters leave to test Jack for that, Taub gets an urgent page and runs off.