Mix Bruce Willis and law enforcement together, and you get a potent mix that's been fueling box-office dollars and action-hero fantasies for the last several decades: The "Die Hard" movies, "Striking Distance," "Hostage," "16 Blocks," "The Last Boy Scout" -- OK, he was a fallen Secret Service agent in that last one, but you get the idea.

Factor in his comedies, however, and the quality drops off a bit. "Death Becomes Her," "North," "Hudson Hawk," "The Kid" -- ouch.

Now, Willis is hoping one genre's success blends into the other, as he's playing a funny cop for the first time in his lengthy career in the Kevin Smith-directed "Cop Out," co-starring Tracy Morgan, which opens this weekend.

"I've played a few cops," Willis grinned when we talked to him recently.

Asked if there was any new territory to mine at this point, Willis gave us one of his trademark straightforward answers: "No."

To him, the reason for doing "Cop Out" -- a film about two mismatched officers trying to recover a stolen baseball card -- was that although John McClane and his other men in uniform have always had a sense of humor, they've never just attempted to be flat-out funny. His character in this film, a veteran NYPD officer named Jimmy Monroe, certainly isn't a clown but gets his fair share of big laughs.

"The only thing that's fun and interesting that came out of this film for me is getting to become friends with Tracy Morgan," he said of his co-star. "And being able to say, with all validity and all honesty, that I get to talk about one of my films that's supposed to be a comedy and go, 'This is really funny.' "

Although Bruce didn't name names, something tells us that he was a bit unhappy with how some of his old "comedies" turned out in years past. But with "Cop Out," he said, he can recommend it in good conscience.

"Everybody is really funny in it," he said, adding that the film's "Lethal Weapon"-like ad campaign doesn't really do it justice. "And while you may hear it talked about as a cop-buddy, action/adventure film, don't be fooled by the advertisements."

Check out everything we've got on "Cop Out."

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