‘Way, Way Back’s’ Liam James finds a way to keep life normal

In a heart-rending scene from Fox Searchlight’s “The Way, Way Back,” 14-year-old Duncan is asked to rate himself on a scale of 1 to 10 by his mother’s emotionally cruel boyfriend. A “6,” the boy grudgingly replies after some thought. You’re more of a “3,” the boyfriend retorts, delivering the blow Duncan knew must be coming.

When Liam James, who plays Duncan in the film opening this holiday weekend, rates himself, he has a little more fun with the idea. The 17-year-old actor, who also has recurring roles on AMC’s “The Killing” and USA’s “Psych,” plays down his rising star.

“I’m definitely a solid 4.5 with my eyes,” he says of his one blue eye and one green, “and a 3 without.”

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And while the Vancouver, Canada, native is having a laugh, it’s nice to see a newly made celebrity stay so grounded. The film is the teen’s first starring turn and has had him crossing the country for press junkets and high-profile events, to which he has invited his family and high school friends. Since his returning to school, some of his classmates have commented on his budding career, James says, but unlike that other Canadian star Justin Bieber, everything has stayed pretty normal at home.

“A local newspaper where we were filming in Boston called me the Justin Bieber of Canada. I don’t think they realized Justin Bieber is from Canada,” James says. “I hope someday I can just be the Liam James of Canada,” he adds.

In “The Way, Way Back,” Duncan is an awkward teen struggling to deal with his parents’ divorce and his mother’s decision to move on. His mother (Toni Collette) takes him on a summer vacation with her boyfriend (Steve Carell) and his daughter (Zoe Levin), to their beach house. As Duncan struggles to fit in, he finds an unlikely group of friends working at the local Water Wizz Water Park, including park manager Owen (Sam Rockwell).

Playing alongside Rockwell, one of his acting heroes, as well as the rest of the well-known cast, James says he found it difficult at times to play the sullen and sulky Duncan. He was having too good a time.

“Ever since I was 9 or 10 I’ve liked him,” James says of Rockwell. “I saw him in ‘The Green Mile’ and I still just don’t even understand how you could play such a role.”

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James says his “always embarrassing” mother, Bonnie, came into his room playing the theme song for “The Way, Way Back” the day they heard he had landed the role to let him know he’d be playing alongside Rockwell. He said he was shocked and excited at the news.

“It was such an amazing experience,” James says. “Now I’m really proud to call him my friend.”

Just as Duncan finds support and encouragement from Owen in the film, James says there existed parallel encouragement and advice between the actors off-screen. From warm-up exercises to hanging out on set, the two developed a friendship that translated onto the screen.

“He was so into making me perform the best I could,” James says of Rockwell. “Him being so great to me really strengthened our bond in the movie.”

Another hero in James’ life, his father, Derek, has encouraged and influenced him throughout his acting career. The former Olympic wrestler not only taught James how to pin someone on the mat, but how to fight for other things in life.

“Because of his wrestling, he’s had many injuries and things he’s had to deal with, but it doesn’t hold him back,” James says. “All my determination has come from him. I’ve never seen him give up on anything. Any time I’m tired I think of him and I push through it.”

Though his career is blossoming, James says he still has not been able to out-wrestle his father, one of his ultimate goals. “I try every day to beat him up,” James says with a smile, “I’m getting close. I will one day — when he’s like 95.”

dana.ferguson@latimes.com