James Cagney

The original Public Enemy.

"You dirty rat!"

—Not James Cagney

James Francis Cagney was an American film actor most famous for gangster roles in the 1930s and 40s, as well as for his alleged Catch Phrase. He starred in some of the best gangster pictures ever made, including Angels with Dirty Faces, White Heat, The Roaring Twenties, and The Public Enemy, which is unfortunately mostly remembered for a scene in which he shoves half of a grapefruit into a woman's face.

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Tropes associated with James Cagney include:

• All Girls Want Bad Boys
• Badass in a Nice Suit
• Can't Get Away with Nuthin': His characters almost always got their comeuppance, largely due to the encroaching Hays Code and to maintain Plausible Deniability about "glorifying violence."
• Damn, It Feels Good to Be a Gangster!
• Do Not Do This Cool Thing: Disclaimers aplenty.
• Escapist Character
• Even Bad Men Love Their Mamas
• Evil Is Cool: Even if the studio pretends that they think it isn't.
• Jerk with a Heart of Gold
• Memetic Badass: was a Real Life street fighter and amateur boxer. He would insist on doing his own fight scenes in movies.
• Momma's Boy
• Media Watchdogs: A lot of his best movies were made in the early days of the Hays Code, when you could still get away with a little bit more. As the code grew in power, subsequent rereleases of some of his films had objectionable material cut. Most notably, The Public Enemy had next to no violence cut from its rereleases -- but vague allusions to sexuality were.
• Our Lawyers Advised This Trope: His movies often come with a disclaimer decrying violence to deter accusations of glorifying violence. Warner Brothers maintained that gangster pictures were meant to serve as a warning, but no one was fooled. (Not that anyone was complaining, though...)
• Self-Made Man
• Typecasting: as the bad guy
• Villain Protagonist