James Evan Wilson, M.D., is a fictional character on the Fox medical drama House. He is played by Robert Sean Leonard. The character first appears in the show's pilot episode when he introduces a medical case to Dr. Gregory House, the protagonist of the show. Wilson is Dr. House's only true friend, and frequently provides him with consultations and aid. Wilson is the head of the Department of Oncology at Princeton-Plainsboro Teaching Hospital. During the show's run, the characters of Dr. House ...