71. ROBERT WALKER
Strangers on a Train (1951)

What an epitaph: Walker died suddenly, at age 32, the year Strangers was released, after a history of emotional problems. He'd played chipper types credibly, but never as wittily or well as he played Bruno Antony, an unstable, petulant, unmistakably gay psychopath who stalks a tennis pro and murders his wife, then demands that the man commit a reciprocal killing. Peak moment: A kiddie gets in his way, so Walker pops his balloon.