Best known from last year's Confessions of a Dangerous Mind, indie actor Sam Rockwell always needs a little help from wardrobe to fulfill his thespian potential. For some reason, he donned a shower cap — borrowed from his hotel bathroom — to plug his role as flashy con artist Frank in Matchstick Men (opening Friday). "I do all of my interviews in character," the goofball cracks. In fact, Rockwell credits Hawaiian shirts and silly hats for his ability to shine opposite Nicolas Cage in this film.

"I was going to make [Frank] really sloppy and have stains on my shirt," says Rockwell, who'd hoped for an Odd Couple element to Frank's interaction with Cage's obsessive-compulsive Roy. "And then, [director] Ridley Scott said, 'I want you to look kind of flamboyant, like you spend too much money on your clothes.'

"It's kind of stylish-no-taste," he explains of his on-screen look. "Somehow, those clothes — as ostentatious as they are, as ridiculous as they are — actually look kind of cool."

Frank needed an über-charming air to match his look, so Rockwell consulted a real-life cop who'd arrested many such flimflam men. "He gave me a videotape with a re-enactment of an ex-con doing these phone scams," the actor recalls. "[The criminal's] voice quality was amazing. I copied it in the beginning of the movie: 'Congratulations, you just won a fabulous prize!' People respond to that, I guess."