Robert De Niro, who's been called the greatest actor of his generation, can play dark and violent one minute, and "Meet the Parents" the next.



The two-time Oscar winner has played a variety of roles in his 70-odd movies over the past 40 years, but the films we remember best are the ones where he terrified the hell out of us -- or made us laugh our asses off.



In honor of his newest comedy, "Dirty Grandpa," we've ranked his 17 most (and least) intimidating roles.