S1, E22: House insists he can handle things when Stacy (guest star Sela Ward), the woman he once loved, asks him to diagnose Mark, the man she married. When Mark’s tests come back normal yet symptoms show that his brain is dying, the puzzle may be one that even House can’t solve. While Wilson worries about House’s emotional well-being, the team is blown away by his over-the-top demands. As House struggles to put his emotions aside and solve the case, Cuddy adds to his dilemma and offers Stacy a reason to stay.