Hollywood fame is a fickle beast, and it's the rare star who's able to keep his/her career viable for any length of time. The 22 actors and directors we've highlighted here are among those whose careers have stumbled - some of them badly - to the point where their respective futures as major industry players have become an open question. Some are closer to the brink than others, but all of them have suffered enough recent setbacks to jeopardize their stock in Tinseltown (or, in one person's case, their stock with sci-fi loving film fans). Will the individuals profiled here continue on their losing streaks to the point where there's no hope of recovery, or will they break out with a hit film or critically-acclaimed performance just when they need it most? Of course, it's hard not to root for the latter scenario in all of their cases; as the saying goes, everybody loves a comeback.