Oncologist Wilson’s first name in House M.D. is James. Dr. James Wilson, played by Robert Sean Leonard, heads the oncology department at Princeton-Plainsboro Teaching Hospital and is Gregory House’s closest friend.
Wilson acts as a moral and emotional counterweight to House. He often challenges House’s decisions, helps interpret the consequences of House’s behavior, and remains involved even when House’s actions threaten patients or colleagues. Their friendship is one of the series’ main continuing relationships.
Wilson’s professional specialty is oncology, the branch of medicine concerned with cancer. His work gives the show access to patients with serious disease while also establishing a contrast with House’s diagnostic role.
The character is usually addressed by his surname, which can make his first name easy to overlook. “James Wilson” is distinct from Robert Sean Leonard, the actor who played him throughout the series.