Grade: 3.5/5.0

“Brigsby Bear” is a really charming movie — it just happens to be about a kidnapping. Mostly strange, but very endearing, this new release disarms with its unconventional subject matter, light tone and tender affection for storytelling. Brought to life by childhood friends Kyle Mooney and Dave McCary, both of “Saturday Night Live” (Mooney is a cast member; McCary is a writer and segment director), “Brigsby Bear” explores friendship, film and their power to unite and heal.

James Pope (Kyle Mooney) is a twenty-something man who shares an isolated, insular and ritualistic post-apocalyptic life with his parents (Mark Hamill and Jane Adams). Trapped in their desert bunker by the threat of poisonous gases outside, James spends his days getting homeschooled by his mother and crafting elaborate theses about the universe within his favorite television show.

His only connection to the outside world, “Brigsby Bear Adventures” is little more than a low-budget children’s television series. Its star — a giant talking animatronic bear named Brigsby — fights against the forces of evil for 736 whole episodes, all while offering James such timeless proverbs as, “Curiosity is an unnatural emotion” and, “If you’re feeling romantic emotions, only touch your penis.”

James’ access to “Brigsby Bear Adventures” and his sequestered lifestyle are shattered one day by the intrusion of the FBI, after which he learns that his “parents” are really not his parents at all, but two kidnappers who abducted him when he was a baby. More shocking to James than this revelation, however, is his discovery that no one else in the world knows about his beloved “Brigsby Bear Adventures.” Only a little disturbed, James sets out to educate the world on the greatness that is “Brigsby Bear Adventures,” memorializing the final chapters of Brigsby’s story on film while trying to navigate the social codes of a world that does not share his cultural lexicon.

Despite the darker leanings that this summary suggests, “Brigsby Bear” is actually a fairly lighthearted movie. Less about the trauma of James’ isolation from the rest of the world and more about his passion for Brigsby, storytelling and film, “Brigsby Bear” weaves a narrative around pain without getting bogged down by it. Though Brigsby’s shadow and James’s own past loom over the film, its major plot points actually center around James’ adventures and mishaps in amateur filmmaking.

Beyond the trauma of the film’s first fifteen or so minutes, nothing bad happens in “Brigsby Bear.” James doesn’t even seem dramatically affected by the revelation that he was raised for more than twenty years in captivity. Rather, his determination to revive “Brigsby Bear Adventures” in the form of a movie — to spread Brigsby’s positivity — occupies James’ mind so entirely that sadness does not even seem to color his frizzy-haired, goofy visage.

A film that treads the line between saccharine and sad, “Brigsby Bear” is filled to the brim with tiny interactions that resonate with their poignancy. There’s the moment when James’ biological sister Aubrey (Ryan Simpkins) offers to make James a playlist, and he responds cautiously, but excitedly, “I’ve always wanted one of … those!” Or the few times that James turns to Google for aid in his movie-making adventures, and ends his search by thanking the search engine.

“Brigsby Bear” — perhaps surprisingly, given its creators — does not aim for major laughs. When it’s humorous, the jokes are quiet and unobtrusive, as when James learns a bit of cool, new slang at his first-ever party and starts calling everything “dope as shit.” It dances toward the dark — it is, after all, a film about a man for whom an entire television show is exclusively produced to keep his curiosity at bay and persuade him from trying to escape captivity. The film has distinct notes of sadness running behind it all, like a low-grade fever.

All in all, though, “Brigsby Bear” does not ask for much. It earns more chuckles than belly laughs, and it’s more strangely endearing than it is sad. More than anything, it’s quirky and humorous, and aware of both of those things. But it’s artful, melancholy and sweet — as much an exploration of James’ education in the real world as it is a tribute to film and friends. (Is it any wonder that it was a hit at Sundance?)