Can people relive their youth? Many dream about returning to an especially happy time in their childhood or adolescence, if only for a moment, but what if one’s early years were unhappy and didn’t turn out the way one hoped? This is one of the questions asked in a fascinating new documentary/animated film, “My Old School.”

The setting is Glasgow in the early 1990s, where a gawky new student from Canada arrives at Bearsden Academy for his final year of secondary school (a catchall title in the U.K. for both middle and high school). Most of his fellow students, seen on-camera as middle-aged adults, remember noticing that he was a bit long in the tooth, but they readily believed that his mother was a touring opera singer who tragically died in a car accident and that he’d come to live in Scotland with his grandmother. 

The boy’s name is Brandon Lee, just like that of the up-and-coming-actor and son of the legendary Bruce Lee who died at age 28 in 1993, a short time before this boy enrolled in the school. The viewer wonders whether this is coincidence or contrivance.

From the outset, we learn that “Brandon Lee” will not be seen, only heard. Yet instead of filming the man in shadow or having his face blurred, the director, Jono McLeod, decided on having Scottish actor Alan Cumming lip-synch Brandon’s reminiscences. It’s a bold move because as effective as Mr. Cumming is, he’s almost no match for the real-life non-actors who are interviewed — those former students who knew Brandon when he was at the school and who come off as appealing, idiosyncratic individuals. Albeit with some very strong accents.

With the setup done, the narrative gains some momentum as Brandon excels in every class, makes a few friends, and even stars in the school’s production of “South Pacific.” Most of these developments are portrayed in the film via charming animated sequences, with a comic-book style of clean black outlines around figures and objects, subtle coloring, and the application of silhouettes and layered lighting. 

Recent biographical documentaries such as last year’s “Flee” have employed the visual language of animation to deal with serious events and subjects. “My Old School,” with its relatively comic tone, mixes moving drawings with talking heads and archival news footage to create a very enjoyable viewing experience — one that only hints at deeper concerns. 

The recounting of “the good times” reaches a delightful crescendo in a montage of typically teenage moments set to Pulp’s “Do You Remember the First Time,” an ironic reference of what we’re to find out later. For in the next section of the movie, fissures start to appear in Brandon’s story; it’s disclosed that his driver’s license has a different name on it and that he may have two passports. 

A trip he takes to the Spanish island of Tenerife with three girls brings it all to a head: He’s not Brandon Lee but Brian MacKinnon, a 32-year-old man. This is where the movie tiptoes around certain issues, such as the moral and ethical question of an adult man going on vacation with three teenage girls. Legally, we are informed, the girls were of age under Scottish law, but the director never interrogates Mr. MacKinnon fully on his motivation. His “bizarre” behavior is simply chalked up to him seeking friendships.

More surprises unspool as the movie illustrates Mr. MacKinnon’s life in the mid- to late 1970s, when he was initially in secondary school and apparently not as popular as during his second attempt. He’s such an unreliable, delusional narrator of his own life, though, that viewers may well question everything being presented. When actual footage and photographs of Mr. MacKinnon in school in the 1990s appear on-screen, it’s revelatory because the notion that many folks believed him to be a young man becomes concrete, for he did look somewhat youthful and naïve in his early 30s.  

So can one relive and improve upon one’s early life, like in the Drew Barrymore romcom “Never Been Kissed”? “My Old School” is a testament to the idea that one can — or, rather, that someone did. To what extent Mr. MacKinnon achieved this successfully may depend on the viewer’s value of nostalgia and thoughts regarding the nature of his ultimate goal. 

Tantalizing as the question is, a sequence as the movie wraps up almost suggests that an answer is irrelevant: Clips show his former friends and acquaintances in their current, everyday lives, instead of just talking directly to the camera, and they’re quietly compelling. Like the renowned “Up” series of documentaries but in a much more truncated version, “My Old School” depicts middle age as just as rewarding as early adulthood, even if compromises must be made.