4. House - Lawrence Kutner
Kutner was one of Team House's more easy-going members. Seemingly without the inner turmoil of the other members, he was ready to try new things when it came to treating patients, in some ways making him almost like House. We found out later in the show he was adopted at age six after his birth parents were shot in a convenience store robbery. He slowly warmed to his adoptive parents, eventually calling them Mom and Dad. Cue the episode "Simple Explanation." After not showing up for work, Taub and Thirteen go to his apartment to check on him. There, they find him dead of a self-inflicted gunshot wound. The rest of the episode is dedicated to the team dealing with their grief. House tries to deduce whether his death was foul play even though the evidence suggests otherwise. The end of the episode has House looking through Kutner's photos and finding one where Kutner is looking off in the distance saddened, suggesting that Kutner suffered from depression. The reason Kutner was written off the show is that Kal Penn had taken a job at the White House. Still, killing him was lazy. I get that his death causes House's mental health to deteriorate, but there were other ways to accomplish this. With all the other story-lines involving House's mental health, I have no doubt the writers could have come up with some other reason for him going nuts. Kutner could have just resigned his post, and since Penn appeared several other times as a hallucination, it would have been nice for the living Kutner to pop up again every now and again.