Robert De Niro's tough guys may come in all shapes and sizes, but they all have one thing in common: you don't want to get on their bad side. His mobsters like The Untouchables's Al Capone and The Godfather, Part II's Michael Corleone wouldn't think twice before ordering someone to tuck you in with the fishes. But men like Cape Fear's Max Cady and Taxi Driver's Travis Bickle would relish doing the deed themselves. So which De Niro killing machine is the deadliest? Vote below... if you dare.

Don't miss De Niro in The Untouchables, The Godfather, Part II, and GoodFellas during AMC's Mob Week through Sun., Aug. 5.