Bob Hoskins in Who Framed Roger Rabbit
Bob Hoskins had a long and noteworthy career, but he's best remembered for his portrayal of P.I. Eddie Valiant, the alcoholic gumshoe in Who Framed Roger Rabbit. Hoskins spent hours each day talking and acting with his imaginary co-stars. Spending eight months communicating with fictional characters would take a toll on anyone's psyche, and Hoskins wasn't immune.