If you’re on social media (or even just frequent pop culture news sites), you can’t fail to have noticed that Wednesday just passed was “Back to the Future Day”, the exact date Marty McFly and Doc Brown (and Marty’s girlfriend) travel to in Back to the Future Part II. As one of the many, many (many) things that went on to mark the occasion, Netflix debuted this crowdfunded documentary worldwide. Apparently it began life as a film just about DeLorean owners, but then expanded to include Back to the Future fans in general, and ultimately features many of the trilogy’s cast and crew talking about the movies themselves, too.

So it’s a “fan documentary”, like, say, Starwoids, Ringers, Done the Impossible, or the one it most reminded me of, Legends of the Knight, This focus has not gone down well with some viewers: there’s quite a lot of criticism on Letterboxd from people who clearly expected something else entirely. Far be it from me to judge (haha! S’exactly what I’m about to do), but I didn’t read up much on the doc before viewing and I’d managed to be aware it was about the movie’s legacy and its fans, so I’m not entirely sure what they expected. If you’re not interested in a documentary about a movie’s legacy and its fans, maybe don’t watch a documentary about a movie’s legacy and its fans?

That said, it does begin with a hefty behind-the-scenes making-of type section about the film in question. Interviewees including Bob Gale, Robert Zemeckis, Steven Spielberg, Michael J. Fox, Christopher Lloyd, supporting cast members, production crew, and at least one studio executive, talk us through the genesis of the project, the travails of getting it greenlit, some of the making of the first film (not least the recasting of Eric Stoltz), touch on their imaginings of 2015 for Part II (not least the famous hoverboard), and only mention Part III in the context of it being the end (reiterating that there are no plans for either Part IV or any kind of remake).

Then it moves on to the fans — what the film means to them, and what that’s led them to do. Those we meet include a couple who travel around the US in a DeLorean fundraising for Michael J. Fox’s charity; the team of aficionados who restored Universal Studios’ decrepit display DeLorean; the family of collectors who own the only film-used DeLorean that will ever be in private ownership; a guy who built a mini-golf course in his yard with a Back to the Future-themed hole that he’s used for charity events with some of the films’ cast; the people who have had some success developing a real-life hoverboard; and the guy who set up a fansite that was so good it became the official site, and is now regularly employed as an official consultant about the films, not least for the rafts of merchandise that comes out these days. We also get a look at the Secret Cinema event in London from a year or two ago that made headlines for all the wrong reasons. Naturally, none of that gets mentioned here (in fairness, because it has nothing to do with Back to the Future itself).

Finally, there are some “famous” fans: Adam Goldberg, who appears to have created some US comedy show I’m not familiar with that had a Back to the Future-themed episode once; and Dan Harmon, who created Community (which this week was revealed to have helped Yahoo lose tens of millions of dollars, of course) and some animated show that the makers of the documentary clearly assume you’re familiar with (I’m not). Harmon comes across… well, he ultimately doesn’t come across very well, let’s leave it at that.

Some consumer advice, if you do intend to watch it on Netflix: someone technical has clearly messed up, because the title cards and end credits are completely black, and interviewee IDs flash up for half a second each on a subtitle track. Obviously it doesn’t ruin the overall flow (unless you really want to know people’s names and jobs), but it’s a shame.

That glaring error aside, Back in Time is not a bad film, provided you know what to expect. It’s a shade too long and the storytelling is occasionally a little jumbled, but there are some nice interviews and stories — hearing Michael J. Fox recount the Royal Premiere where he was sat next to Princess Diana pretty much makes the whole exercise worthwhile.

Back in Time is available on Netflix now.