Bob Marshak / Paramount Pictures
As Tommy, Downey tries to keep his sister Claudia's (Holly Hunter) spirits up during a chaotic Thanksgiving gathering. But off screen, Downey created his own chaos: "I was altered as often as not. That was the first time for that on screen. I would spin through a scene like a whirling dervish. Everyone was like, 'What just happened?' but I was off the set and going to lunch."