Operation Avalanche is a fake documentary about of the Apollo 11 moon landing, in a parallel universe of sorts where the event was faked. At that said, it's a very real movie, which was also a real Sundance hit.
Here's the official description of the film:
1967: the height of the Cold War. The CIA suspects there is a Russian mole inside of NASA, sabotaging the Apollo program. They send two young agents on a mission to go undercover, posing as documentary filmmakers to capture NASA's race to the moon. The real mission — use their access and technology to hunt down the leak. But what they discover is far more shocking than soviet spies… Their government may be hiding a secret about Apollo that could define the decade, and the White House will stop at nothing to silence anyone who learns it.
If you feel like you're experiencing a bit of deja vu, chances are you're remembering that other film about faking the moon landing, called Moonwalkers, which starred Rupert Grint and Ron Perlman and was released in America this past January. That film was a wacky comedy, but Operation Avalanche is not — it's more like a found footage conspiracy thriller set in a parallel universe where the moon landing didn't happen. As I mentioned above, Avalanche also has the benefit of having some rave reviews from when it premiered at Sundance, which Moonwalkers, uh, did not.
The film will hit theatres on September 16. For the record, this trailer premiered on io9 at 4:18 pm ET, July 20, 2016 — exactly 47 years after Apollo 11 touched down on the moon. Or a cunningly built soundstage. One of the two.