Being involved in the Hollywood machine must be precarious business. You spend your life as a nobody and then, the moment you taste success, a disorderly queue develops insisting you're the greatest genius who ever lived. You are special, they say. You are exceptional. Let us buy you a drink and back-pat you some more. Will you sign this? Please? Go on. Acting or directing must be a lot of fun, and clearly each discipline requires a lot of talent and hard work, but there is something about film-making which doesn't agree with the human ego. Too much praise is bad for a person, and if you do a good job, Hollywood will deliver cacophonous praise on a stream of private jets. The actors and directors on this list have all tasted success at one time or another, be it critical or commercial (sometimes both). Each of them, in their own way, failed to deal with the hype bestowed on them. This might take a variety of shapes: their own pretensions resulting in an inability to recapture former glories; money squandered on an inevitable drug habit. You get the gist. Some have begun to rebuild their careers, others are right in the middle of a movie-making tail-spin. For many it's too late; they've sunk without a trace and it looks like things will stay that way.