New rule: Moving forward, any mob and/or gangster movie or TV show must include British actor Stephen Graham. Need convincing as to why? Catch up with HBO's Boardwalk Empire, which features Graham killing it as Al Capone, playing the infamous criminal as a combustible tough guy who conceals an underlying, family-triggered softness.

And, wouldn't you know it, Graham's work on Boardwalk Empire isn't a one-shot deal. In Michael Mann's John Dillinger (Johnny Depp) versus Melvin Purvis (Christian Bale) flick Public Enemies, Graham beasts out as Baby Face Nelson, Dillinger's craziest associate. Like the real-life gangster he portrays, Graham's performance is a study in contrast: He looks harmless enough, but give him a gun and as much as a side eye and he'll murder you with unbridled, easily detectable pleasure.