Matt Damon (left) and director Cameron Crowe on the set of WE BOUGHT A ZOO. (Neal Preston)

As an actor with nearly 50 major motion pictures on his résumé, Matt Damon thought he had encountered every directorial trick in the book.

Then he met Cameron Crowe. The writer and director behind “We Bought a Zoo” — Crowe’s latest film and the one that teamed him with Damon — did something that was new to the veteran movie star. He played pop music while the cameras were rolling, an approach that, in one scene, caused Damon to weep openly and repeatedly over the loss of his character’s wife.

“The music was literally what just pushed all of that rational thought out of my brain and just pulled what was left out — all, kind of, the guts of it,” Damon says during a recent telephone conversation from New York. “And that was there and available to me all day long. It really felt great to me as an actor, and I know that’s because of the director.”

“We Bought a Zoo” — a film about a widower who does exactly what that title suggests — marks the first time that Damon, 41, and Crowe, 54, have worked together. But during a 40-minute phone conversation with the two men — both sons of teachers, fathers, Oscar-winning screenwriters and strong believers in movies that earn their happy endings — they sound like longtime simpaticos.

“The list of guys who have been able to bring stuff that I’ve written to life is so short,” Crowe says. “When you see the words coming to life with the kind of depth and fun that Matt brings to it, it’s addicting.”

Says Damon of his director, who has a reputation for being an eternal optimist: “I imagine the Dalai Lama might be a little more positive. But he’s the only one I can think of.”

It makes sense somehow that the upbeat Crowe and Damon — a happily married movie star who spends his spare time working for, an organization he co-founded to help bring clean water to people in need — would become co-conspirators in the war against cynicism. “We Bought a Zoo” might be the most unashamedly uncynical movie of the holiday season.

In it, Damon plays a character based on British writer Benjamin Mee, author of the book upon which the film was based. Within the context of the movie, he’s a classic example of the signature Crowe hero: the good-hearted, eminently quotable Everyman who reaches a crossroads in his life and opts to take the risky path less traveled.

In “We Bought a Zoo,” that risky path involves purchasing an aging zoo and moving his two children to a home that shares land with lions, tigers and bears. It’s Crowe’s first feature since 2005’s critical and box-office disappointment “Elizabethtown” (and his first since his divorce last year from Nancy Wilson of the band Heart). The film is peppered with the filmmaker’s usual aspire-to-greatness dialogue. (“Sometimes all you need is 20 seconds of insane courage,” Damon tells his teenage son in one of the film’s pithier scenes.)

“We Bought A Zoo” is in a unique category among the many December movies bidding for box-office attention. It’s a PG-rated family film that lacks Muppets or animated Chipmunks. It’s an uplifting tale with animals, but no horses that play key roles in World War I. And it’s based on a book, but not a bestseller about a nose-pierced hacker who helps solve a decades-old murder case.

The differences between that last film, “The Girl With the Dragon Tattoo,” and “We Bought a Zoo” were accentuated by a recent public flap between producer Scott Rudin and New Yorker film critic David Denby. In a series of private e-mails that leaked online, Denby defended his decision to break a studio-enforced embargo on reviews of “Dragon Tattoo,” noting that too many serious films are jammed into the final weeks of the year. “We had a dilemma: What to put in the magazine on December 5?” Denby wrote in a message to Rudin, posted by the Indiewire blog. “Certainly not ‘We Bought the Zoo,’ or whatever it’s called.”

“The Denby thing was almost funny to me,” Crowe says of the episode, “because I felt like we were the people sitting at a table at the bar, and this barroom brawl breaks out and they spill onto your table and you get knocked out.” He starts to laugh. So does Damon. “I’m like, hey man, I’m just having a sandwich here and Scott Rudin and David Denby just came twirling across and I got my jaw broken.”

Regardless of what critics may presume about his work, Crowe seems committed to following his instincts. Which made this reporter wonder: Do Crowe’s instincts tell him that perhaps he should write a film that allows three of his previous warriors for positivity — Damon, Tom Cruise (Jerry Maguire) and John Cusack (boombox blaster Lloyd Dobler of “Say Anything ...”) — to work together?

“I love that idea,” Damon says immediately.

“You know, Tom Cruise came to visit the set when we were making ‘We Bought a Zoo,’ and I kind of stood back at a certain point and watched the two of them talking,” Crowe says, referring to Cruise and Damon. “And I had the same idea. It’s like . . . ‘Stay there. Keep talking. I’ll be back with some script stuff in a moment.’ ”