Depressed billionaire Roy Randall consults with a doctor in his mansion. His son Jack is very sick, and the doctor tells Roy that he is getting worse.
Roy goes to Princeton-Plainsboro to demand from Cuddy that House take on his son's case. Cuddy informs House of this, but Foreman still feels threatened by House's presence. Cuddy also tells Foreman that he has to speak about Dibala's case to Morbidity and Mortality conference, dubbed "M&M." This concerns Foreman and Chase.
Cameron lists Jack's symptoms as abdominal pain, fever, dehydration and diarrhea. Seventeen other doctors have treated Jack and have ruled out everything. House wants to start over on him. Cameron feels something wrong in Jack's abdomen and finds that there is a mass in his colon. She tests for Hirschsprung's congenital disorder. Meanwhile, House finds Thirteen at a coffee shop where she tells him she is booking a trip to Thailand.
Although he is improving, Jack suddenly has a violent seizure. Cameron and Foreman rush him to Chase in the operating room so that he can relieve pressure in the skull by drilling holes. The doctors don't know what just happened. The team reviews Jack's MRI. Foreman notices something strange in the brain. House orders a dural biopsy to confirm that it is brain cancer.
Thirteen is in a cab to the airport when she finds out that her trip had been canceled. She confronts House about ruining her trip, but he claims he didn't do it. He doesn't want her around. Later, House asks Foreman if he was the one who cancelled Thirteen's flight but he denies it.
Foreman tells Chase that there is a problem with their Dibala story -- the cholesterol levels in the blood do not match on the tests. Cameron approaches Chase because she senses something is wrong. He admits that there is a glitch with Dibala's case. Chase tries to come up with rationales for the difference in Dibala's blood tests. Foreman tells Cuddy that he does not feel like addressing the M&M conference.
With Jack testing negative for brain cancer, House suggests that the cancer is elsewhere. When they tell Roy about the cancer, he says it is his fault. He believes it is punishment for being successful in business. Jack seizes again. The team no longer thinks Jack has cancer, but they consider abdominal epilepsy.
Cameron points out red marks on Jack's chest. House decides to treat him for polyarteritis nodosa, but then he realizes that it is Degos disease. House gives Roy the bad news. Degos is incurable, and Jack has a day left to live.
After a night of research, Chase tries to confess to Cuddy what he did to Dibala. She realizes they are trying to cover themselves, but she doesn't get the whole story. Cuddy then finds Roy ready to put up his assets to save his son. He believes that he cannot have good fortune in all areas of his life. If he releases all his money, Jack will be healed. But suddenly, Jack starts to flatline.
Thirteen comes to the hospital to see Wilson about her Thailand trip because it was traced to his email. He confesses that he changed her flight. Thirteen still refuses to come back. Wilson knows that House was the one who did it, but keeps that secret from Thirteen. House won't admit to Wilson that he really wants Thirteen around.
House comes up with a diagnostic breakthrough about Jack's heart, and he calls for the treatment of primary antiphospholipid syndrome. House lets Foreman know that Thirteen came to him and Wilson for help, so this means she must not be over Foreman.
Chase finds a report on Dibala that can justify the difference in his cholesterol levels. A previous doctor had given Dibala supplements of niacin-bound chromium. Foreman had nothing to do with it, but who did?
House reads a newspaper headline about Roy going bankrupt for his son, who is now well.
Chase knows that House was responsible for the new information on Dibala. He acknowledges that House will always be in charge.
Cameron wakes up in bed alone as Chase listens to Foreman confidently address the M&M conference. Thirteen boards her plane, ready to leave.