Racoons are funny creatures. Some people regard them as vermin and you don’t want them messing with the house pets, but they’re cute and they’re clever. Sure, they’re bandits, hence the furry masks. Now, there’s a new raccoon in town. He’s genetically modified, he talks, he walks upright, he’s whip-smart, and he’s even more larcenous than the average garden pest. He’s Rocket. He’s voiced by Bradley Cooper and he is one of the reasons Guardians of the Galaxy is one of the most entertaining movies of the year. All of the Guardians—Chris Pratt’s goofy Star-Lord, Zoe Saldana’s intense Gamora, Vin Diesel’s sweet, sweet Groot, and Dave Bautista’s vengeful Drax—are pretty special, but the wise-cracking raccoon is GOTG‘s secret sauce.

People‘s 2001 Sexiest Man Alive made his big screen debut in Wet Hot American Summer, mixed it up with Vince Vaughn and Owen Wilson in Wedding Crashers, and was a key player in the Hangover franchise. But lately Cooper’s had a more serious career: two Oscar nominations in a row for his work with director David O. Russell, Silver Linings Playbook and American Hustle; upcoming are yet another collaboration with Jennifer Lawrence, Susanne Bier’s dark drama Serena, and Clint Eastwood’s American Sniper, in which he plays Navy SEAL Chris Kyle. In November, Cooper will fulfill a long cherished dream when he steps on a Broadway stage to play deformed 19^th-century legend John Merrick in a revival of The Elephant Man. It is becoming a truly serious career, but Cooper is a gifted goofball and so it is a delight to hear him embrace that so fully as Rocket.

Cooper has likened the pint-sized bounty hunter to Joe Pesci in Goodfellas. And, yes, Rocket is a motormouth with anger issues, which may relate to his small stature. Plus, Rocket has reason to be furious, thanks to his very nature. “I didn’t ask to be torn apart and put back together over and over and turned into some little monster!” is how the little raccoon puts it. But with Pesci’s Tommy DeVito, there are a lot of laughs until that rage surfaces in a violent eruption. In contrast, Rocket has a big heart beneath the bluster, expressed most profoundly in his friendship with the tree being Groot, but also emerging in the way he bonds with the other Guardians.

Rocket is also chaotic and unpredictable and snarky, but he’s ultimately a good guy and that snark makes him hilarious. Like his real-world counterparts, Rocket is maddeningly mischievous and can be truly annoying and is also ultimately disarming in his clownish charm. Guardians of the Galaxy wouldn’t be the same without him. Well cast, well rendered, and well served by director James Gunn and Nicole Perlman’s screenplay, Rocket is one of the keys to GOTG‘s success.—Pam Grady