Brent Mason is woken early by his crying baby. He starts to gag over the sink and his wife, Kara, begs him to stay home for the day. Brent leaves the house, but collapses and vomits. He returns home to find Kara in the bathtub with the baby. She's having a seizure and the baby is underwater.
The EMTs wheel Kara and her 4-week old into the ER. Chase goes to work on both of them. Meanwhile, Wilson gloats to House that Cuddy asked him to dinner and he thinks she wants to suck up to him for some favor. House is sure that she's up to something. Cameron has Chase's case from the ER, but she must wait to present to House because Foreman has returned. Foreman is happy to be back at work, but House is skeptical. He asks Foreman to make coffee, and watches as Foreman struggles to open the bag of grinds. Although he still has some spatial analysis troubles, Foreman says his left side/right side reversal is gone and everything else is basically fine.
Cameron brings up the ER case again, but House dismisses the simple seizure diagnosis boring. Foreman calmly and easily diagnoses the epilepsy with elevated calcium levels as either hypertherothyroidism, cancer, or calcium-mediated neurotoxicity. Yet Foreman can't diagnose how the coffee maker works. The ER has already ruled out all of the obvious and simple explanations, so House becomes interested. Cameron suspects Whipple's and House considers vasoconstriction. Chase just thinks it's strep, since Brent is also sick, but he cannot help the team because he is stuck on neonatal intensive care duty.
Cuddy arrives at her office to find House waiting. He wants to know why Chase is in the NICU. Cuddy claims that they are short-staffed there, but House knows that is a lie. He realizes that Chase asked for a new assignment.
Kara and Brent test negative for strep. Cameron jokes about Foreman's health, and he says it doesn't matter because he is alive. His worst case scenario is to teach. Cameron is confused, and she asks about his dreams of landing grants and running his own department. Foreman answers that if he cannot figure out the coffee machine by then, he doesn't deserve the chance.
Chase makes the rounds in NICU when baby Michael Mason begins crashing from a lack of oxygen. At the same time, Cameron struggles with Kara in the MRI. The woman tensed up as Cameron inserted a catheter, and blood went flying. Yet this is not a seizure because Kara's muscles aren't contracting. She is so tensed that her back is completely arched.
The team meets in the NICU to figure out what causes seizures, hypercalcimia and the rigidity. Chase is there, examining x-rays of Michael's lung. He suggests lithium as a cause of all three symptoms. Foreman throws out myluminous meningitis. House likes that and orders an S-PAP and an MRI. Then he advises Chase that Michael's lung problem is bacterial, not chemical. House asks Chase point blank why he doesn't want to work with him. Chase says he just needed a break from the intense pressure. House isn't buying it.
House brings Wilson items from Cuddy's trash -- a receipt from a pharmacy and an empty box of Red Clover. Both doctors know that Red Clover is used for cancer. House observes that Cuddy asked an oncologist to dinner instead of any other doctor in the department. House thinks that this isn't a date but a consult.
Cameron reports that Kara tested negative for meningitis, but she is bleeding into her brain. Foreman, who searched the Mason home, only found a hidden bottle of vodka. Cameron is ready to believe that alcoholism is the cause, but Foreman goes deeper into the history. He thinks that, with the family's growing debt and the new baby, Kara developed conversion disorder where psychological stress presents itself physically. House is leaning more towards alcoholism. Since Kara's tox screen was negative for alcohol, he orders a phenocoma as treatment for DT. Foreman walks out without objection, which irks House. He questions why Foreman isn't defending his point, but Foreman says that House would have overruled him because he had probably considered the father anyway. Besides, Foreman is a changed man.
Brent and baby Michael come in to see Kara before her coma is induced. She apologizes for what she did, but Brent doesn't blame her. Foreman informs House that the happy Mason couple met in AA. Obviously, Kara had a relapse. House looks into Kara's room and sees her with her back to the hall. The baby is missing from the bassinet. He and Foreman race into the room to find her smothering Michael. Foreman pulls her away as House grabs the child. With Michael unconscious, House calls for the crash cart and begins infant CPR.
Foreman explains to Brent that Michael is stable, but the lack of oxygen caused kidney damage. Brent concludes that Kara accidentally rolled over in her sleep, but Foreman says that he witnessed it. Brent refuses to believe it. In her room, Kara tells Cameron that the voices told her that Michael would be better off dead.
When the team reconvenes, Cameron now theorizes that Kara faked the seizure when Brent caught her trying to drown the baby. Foreman thinks the seizure was real. The postpartum made her try to drown Michael but the stress caused the seizure. House wonders why nobody is talking about actual physical illnesses anymore. Foreman thinks he has a point, and offers to draw some blood. This drives House insane. He begs Foreman to start sticking up for himself. He wants Foreman to stress Kara into another seizure. House instructs them to take her off haloperidol, hook her up to an EEG and start flashing lights. If Kara starts twitching, the machine will tell them if the seizures are real.
House wants to know how Wilson's dinner with Cuddy went. Wilson says that it was a real date and that cancer never came up. House asks why he is in the lab doing a PCR test from a spoon. He deduces that it must be Cuddy's spoon from dinner. Wilson admits that he's checking her saliva for cancer markers. House tells Wilson to find him when the results come in.
Chase tells Brent that he needs to start Michael on dialysis. Because of the kidney damage, the boy's potassium level is rising and if it doesn't come down then he will have a heart attack. The stress test on Kara is completely uneventful until Cameron notices that the brain activity is slowing down. Foreman and Cameron look into the room, only to see Kara grasping and sucking. This, combined with muscle rigidity, means encephalopathic delirium. While this is an actual physical illness to work with, the progressive nature of the case means it can't be long before Kara's brain shuts down entirely.
Baby Michael suffers a heart attack and Chase tries to shock him back. The team is stumped for causes. House throws out pellagra and Foreman agrees with it, pointing out that alcoholics have horrible diets and often lack niacin. This starves the brain, which causes everything Kara is suffering from. Chase brings the team the news that Michael is dead.
Foreman pulls Kara out of her coma and asks her a simple question to test her acuity. She is more interested in finding out where Michael is. Foreman informs her that the pellagra was making her believe things that weren't real, and Kara confesses that she remembers doing things to her son. Foreman breaks the news that Michael is dead. Kara wails in agony and then vomits.
Foreman finds blood in her vomit, which is not caused by pellagra. Whatever Kara has is getting worse. Thinking about the dead baby gives House an idea. He finds Brent, who is cradling Michael's lifeless body. House tells him that the baby had the same condition as Kara. Yet House cannot biopsy her because she will bleed to death. House needs the baby, but a resentful Brent won't hand over the child to help his wife. House angrily turns things around on him, pointing out that he was drinking as well. If he made any effort at all to pay attention to what Kara was going through, then he would have picked up on her symptoms before it got this far. Brent agrees to the tests.
House lets Chase know that Michael's body is available for tests, but Chase isn't interested. House then holds up Chase's paycheck and asks why he'd be working in NICU while using his vacation days from House's staff. He wants to know why a rich boy like him need the extra money, especially when his late father left him money. Chase coldly responds that he's not rich.
Before performing the test on Michael, Chase says a prayer for strength. He reports to the group that Michael's intestines show slight villous atrophy. House asks the team how polystyrene treatments could cause flattened villi. Foreman points out that the polystyrene itself couldn't cause that, but House wants them to look at the binding agents. Cameron brings up wheat gluten. Both Kara and Michael had celiac disease, an affliction where the body cannot process gluten. Each time the gluten was introduced to the body, the small intestines were further damaged, until they reached the point where they couldn't receive vitamins and minerals. This led to the niacin deficiency, which created the other problems. Celiac is also why Michael's medicines didn't work. His body couldn't absorb them. Additionally, celiac patients are susceptible to cancer of the stomach lining, which would explain the bloody vomiting.
Wilson announces to House that Cuddy is negative for all cancer markers. House goes to Cuddy's office and tells her that she doesn't have cancer. She's more than a little surprised by the test results, mainly because she didn't know that tests weren't being run. Cuddy's estrogen is too high because she is on fertility meds. Her dinner with Wilson was an audition. Cuddy confesses that she's looking for a sperm donor, not a partner.
Kara refuses treatment. House visits with her and learns that she feels guilty about killing her own son. House assures her that she's blameless because she is now healthy except for the cancer. Kara still declines treatment.