SANTA MONICA. Calif - Sam Rockwell doesn't want to hear "quirky" when describing the characters he has portrayed in his film career. When he hears it, he makes a face as if the Arnold Palmer he's drinking at a beachfront hotel has gone sour.
"Quirky? I don't know if I love that word," Rockwell says, looking for a substitute. "What's another way of saying it? My characters are a little crazy. How about crazy?"
Done. His Justin Hammer villain in 2010's Iron Man 2 and his barmy Billy in 2012's Seven Psychopaths were deeply crazy. Yet in Rockwell's latest role as Owen, a reluctant father figure in The Way, Way Back, he's a only a little bit crazy, with a big heart.
"I like to color with my crayons outside the lines," says Rockwell, explaining his acting philosophy. "I like to keep things off-center."
Rockwell is winning raves for the performance in the Sundance hit (opening July 5 in select cities) written and directed by two of the Oscar-winning screenwriters from The Descendants, Nat Faxon and Jim Rash.
The duo knew they had to find the right kind of eccentric actor for the motormouth manager of a dingy water park called Water Wizz, who takes awkward 14-year-old Duncan (newcomer Liam James) under his wing, much like Bill Murray's camp counselor in 1979's Meatballs.
"It was like who is our Bill Murray? Who is this extrovert who feeds off people's energy but has a good heart?" Rash asks. "Sam is this great character actor who can make this all real and still show the warts and all."
Rockwell says he had to expand his improvisational skills to capture Owen's hilarious, riffing conversational style, which was intimidating since Faxon and Rash were members of the famed LA improv group The Groundlings.
"I've done some improv before, but I'm more of a traditional actor," says Rockwell. "I spit out a lot of dialogue. It was like a stand-up routine, pretty intense."
He had inspirational help from his screen heroes including Murray, Walter Matthau in 1976'sThe Bad News Bears and Richard Pryor from 1981's Bustin' Loose. Rockwell is such a fan of Pryor that he proudly pulls out his scuffed-up AT&T flip phone ("I"m not really a tech guy") and shows a picture of his comedy hero on the tiny screen.
"I've stolen some moves from Richard Pryor and put them into Owen," says Rockwell, looking at the image. "It's a similar kind of character, kind of the affable but grouchy-uncle type."
To complete the transformation, Rockwell cut down on working out ("Owen drinks a bit of beer," he says) while wearing a wardrobe of white tank tops and Hawaiian shirts. The rest was simply surviving the summer shoot at a real Western Massachusetts water park called Water Wizz.
"It was blast. The only downside was being in the sun for 12 hours," says Rockwell. "But you just find some shade and have a slushee and you're good."
He also had help from Steve Carell, who plays Duncan's mother's controlling boyfriend.
"(Carell) does this insidious character really well, it's amazing," says Rockwell. "We could have switched easily, no question. I usually play the bad guy."
But even Rockwell's bad guys tend to have an adorable eccentric side. Witness his psycho from Seven Psychopaths who wore a memorable furry bear. Co-star Colin Farrell bought the hat at roadside gift ship while the actors were on a pre-shooting road trip. Rockwell fell in love and co-opted it for the shoot.
"Colin is still regretting not wearing it himself. I stole a lot of scenes with that hat," says Rockwell. "The hat was upstaging everyone."
Rockwell likely will continue doing the same. He's especially excited about beginning work for a role as a divorce lawyer alongside Keira Knightley in Laggies, and his just-wrapped performance as an ex-Navy SEAL opposite Marisa Tomei in Why Now?!
"They will be unconventional," says Rockwell, lighting up. "Now there we go, that's the word. I like that one."