The only thing scarier than a cult is one that’s actually right. Plenty of cults end in tragedy, but none end in an inter-dimensional god actually saving his followers and destroying the world. (At least not yet.) Of course, the beauty of science fiction is that you can see exactly how that might play out from the comfort of your couch.

In 2020, one movie did just that, and three years later, it’s still the best film to tackle cults this decade — so far. The Empty Man is streaming now on HBO Max, but it won’t be for long. Here’s why you need to watch it while you can, and what, you should know before you do.

Half cult thriller and half Candyman copycat (and half Christopher Nolan-esque mind-bending sci-fi), The Empty Man tells the story of a cult obsessed with a cosmic being known as… the Empty Man. The story is loosely based on the Boom! Studios comics of the same name by writer Cullen Bunn and artist Vanesa R. Del Rey.

The movie opens in the Himalayan mountains in 1995, where four friends are hiking. When one of them falls into a cave, they discover a bizarre skeleton and seem to become traumatized, entering a catatonic state. Soon afterward, a storm arrives and the group is forced to take shelter in a nearby cabin. Things end poorly as The Empty Man’s 30-minute prologue ends and the movie jumps forward to middle America in 2018.

The bulk of the film follows former detective James Lasombra (James Badge Dale) as he investigates the disappearance of his neighbor’s daughter, Amanda. Along the way, he encounters a deadly urban legend and a sprawling cult. All the while, James’ connection to reality becomes increasingly tenuous as he witnesses a series of unnatural events culminating in a twist that will make you question reality itself. I won’t spoil anything here, but trust me, this is a twist worth experiencing for yourself.

The Empty Man was written and directed by David Prior as his first feature film. It’s an impressive debut, and even more so when you know about the drama behind the scenes. The studio executive at Fox who supported the film left during production, and after filming began in South Africa (for budget reasons) the costumes got stuck in airport customs.

Even after filming was finished, the battle wasn’t over. An early test screening almost derailed the movie entirely. “It must be famous for how low the score was,” Prior told Thrillist in a 2021 interview.

The Empty Man also got stuck in limbo after the Fox-Disney merger. In a fun bit of trivia, Prior notes that his movie is “the actual last Fox movie with the original logo, which is both sad and a point of pride. We’re at least a footnote in the history of 20th Century Fox.”

When the film finally did arrive in theaters, it was in 2020 at a moment when no one was going to the movies. The Empty Man came and went without much notice and mostly negative reviews due to a misleading marketing campaign. But it finally got a second life on streaming.

Once it leaves HBO Max, it’s unclear what The Empty Man’s future will be. While the movie is available to buy digitally from Amazon, iTunes, and all the usual storefronts, there’s no physical Blu-ray you can own forever. It’s possible the film might show up on the Disney-owned Hulu, but if you’ve been meaning to stream The Empty Man, your best bet is to do it now — before it’s too late.

The Empty Man is streaming on HBO Max through the end of September.