Carl Reiner will guest star on the fifth season finale of House.
In the May 11 episode, Reiner (most recently seen in the Ocean's 11 trilogy) will portray a clinic patient Cuddy uses to get House's attention, forcing him to complete his clinic hours by treating the character.
In other finale news: House treats a man whose left and right brain operate independently. He lives with split personalities and has no control over his actions, making treatment a challenge.
In other words: right in House's wheel house!