The Envelope: What do Brian Wilson, a martial artist and an activist priest have in common? John Cusack

John Cusack’s 2015 output might seem surprising … until you look closer to see the pieces of him that belong in the portraits he’s done of an emotionally troubled musical legend, a Roman soldier in a martial-arts adventure and a firebrand Catholic priest.

He played Beach Boy Brian Wilson in his post-retreat-from-society days in “Love & Mercy.” Some questioned his casting because of the lack of a physical resemblance — but if you recall Cusack’s adaptation of “High Fidelity,” his deep knowledge and appreciation of pop music history made him a harmonious choice.

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“In ‘High Fidelity,’ the only thing the three snobs [who work in the movie’s collectible-vinyl record store] would agree on was that ‘Pet Sounds’ was in everybody’s Top Five. I think anybody who thought of themselves as someone who understood music or the importance of rock ‘n’ roll knew about Brian Wilson,” says the actor, whose feeling and centered performance make him an awards contender.

“When you go back and listen to the ‘Smile Sessions,’ you can hear him saying, ‘Third cello, one inch off the mike. Second trombone....’ Hearing it and miking it in a room and capturing it. It’s extraordinary. It’s hard to underestimate his power as a creative force.”

Then there was “Dragon Blade,” the Jackie Chan actioner Cusack describes as “a crazy, big, epic sword-and-sandal thing. Roman and Chinese DNA were discovered long before they thought Rome had ventured that far, so they created a story around that, along the Silk Road.”

John Cusack in a martial-arts movie?

Well, yes.

“I’ve been doing martial arts for 30 years,” says the actor, who notably fought in “Grosse Pointe Blank” with his longtime sensei, Benny Urquidez. “Dragon Blade,” he says, “was more swords, but still, if you’re a martial artist, you have to go to the Gobi desert to do a big fight scene with Jackie Chan.”

And then there’s the new Spike Lee “Lysistrata” adaptation, “Chi-Raq,” in which Lee transplants the ancient Greek play’s notion of a sex strike to force peace to the violence-torn streets of modern Chicago. Cusack’s character, a priest named Mike Corridan, is based on Father Michael Pfleger, a real-life cleric who has been fighting the good fight there for decades.

“I’d known him in Chicago because he’s a big-time activist,” says Cusack, who always seems aware of the social context of his roles. “He’s been doing incredible stuff,” says the actor who blew out his voice during a house-on-fire sermon scene.

(Ricardo DeAratanha / Los Angeles Times)

“Everything we did in our sermon was taken from [Pfleger]. That’s his voice. That’s his church, that’s his place. His congregation. Most of the women there who had lost their children, they’re the ones putting their pictures up of their children at the end of the movie. Over 2,200 people have been shot there this year, 2,200. More than 400 homicides.”

In “Chi-Raq,” Cusack brought the fire. In “Dragon Blade,” it was the steel. And in “Love & Mercy,” he had a whole musical kaleidoscope turning in the head of someone who had come to keep almost everything inside. Wilson’s plight had been mythologized as the classic rock ‘n’ roll burnout.

“One of the reasons [Brian] wanted us to do the film was to tell the truth about mental illness,” says Cusack. “He was schizo-affective, which meant he had auditory hallucinations. He was absolutely abused, misdiagnosed. I think he really wants the movie to help people … take some of the shame away from having a condition. I think he wanted to correct his legacy.”

Costar Elizabeth Banks, herself a contender for her nuanced portrayal of Melinda Ledbetter, the woman the fractured Wilson would come to marry and heal with, said Cusack is “very committed. He still loves character and delving in and trying to disappear. I think he’s beautiful.”

Cusack says most of what he gleaned from the rock legend came from “just being around him,” seeing “how he was around people, how he navigated the world.

“Brian, you don’t know if he’s kind of in his own world because he can’t get out of it or he’s tired of everyone needing the ‘Brian Wilson moment’ and it’s easier just to stay in his own world. So he’s a bit of Cheshire cat that way.

“He just doesn’t lie. Don Henley came and said, ‘Could you please sign this record, it meant so much to me?’ ‘OK, OK. “Dear Don, thanks for all the great music” ’ and he crossed out ‘great’ and wrote, ‘good,’” says Cusack, laughing. “Don Henley, like, framed it.

“It was an incredible act of courage just to put his life back together. He’s such a wild combination of incredibly fragile and really, really tough.”

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