Episode 49 of "House"
s03e03 Informed Consent

The ketamine has worn off and House is back to using his cane and doesn't want to talk about it. His new patient is Ezra Powell (guest star Joel Grey), a renowned pioneer in the field of medical research, who collapsed in his lab. House puts Ezra through diagnostic rigors, but the team is unable to come up with a conclusive diagnosis, and Ezra's health continues to deteriorate. Becoming increasingly debilitated, Ezra ultimately demands that the team stop the litany of medical tests and help him end his life. The team members have divergent opinions on the morality of helping Ezra die, especially since the possibility of a cure is still in question. The moral dilemma of whether to assist in his suicide and abide by Ezra's wishes, or to ignore what their patient wants drives the team in very different directions. Meanwhile, the teenage daughter of a clinic patient has developed a crush on Dr. House.