An Alzheimer's patient visits Princeton Plainsboro as part of a hospital-sanctioned drug trial. When he inexplicably suffers violent blood vomiting and an increasingly explosive temper, the team unravels a deeper marriage conflict between the patient and his dutiful wife. Meanwhile, when Wilson tells House about a patient who has never had sex with her husband of 10 years, claiming A-sexuality, House makes a wager that there has to be an underlying cause. Also, House and Foreman butt heads.