One of the king-daddy conspiracy theories of all time — right up there with the “grassy knoll” and Area 51 — is the notion that the Apollo 11 moon landing of 1969 did not actually happen and that it was created on a movie studio set as government propaganda. This theory grew to the point that fevered minds were pointing the finger at Stanley Kubrick, the director of sci-fi epic “2001: A Space Odyssey,” as the man who faked the footage. Some even claim that he was leaking clues to that effect in his films. (See the documentary “Room 237″ if you want to head down that rabbit hole.)

The theory hasn’t held up well, with little evidence to back its claims, but it was rather prescient in suggesting that film technology was getting to the point where images could no longer be trusted as representations of fact, a problem that has magnified tenfold since the advent of the Internet and Photoshop — just try searching online for “Fukushima” and “deformed fish.”

While 1977’s “Capricorn One” treated this topic seriously, new film “Moonwalkers” employs it as pure stoner comedy. It’s a clever marketing move, really, since stoners rank second only to clinical paranoiacs in their love of conspiracy theories and their belief that no neat, clean, obvious explanation should suffice when you can have a tangled, convoluted, gargantuan one instead.

“Moonwalkers” is the debut of French director Antoine Bardou-Jacquet, and stars Frankenstein-faced Ron Perlman (“Sons of Anarchy”) as an addled CIA operative named Kidman suffering from ‘Nam-induced PTSD. He’s tasked by his higher-ups to hire Kubrick, then known for having produced the most realistic-looking space-travel special effects on film, and to have him prepare fake footage of the lunar landing just in case the actual mission fails. Kidman arrives with a bagful of money in Swinging London — an era “Moonwalkers” embraces more cartoonishly than any film since “Austin Powers: The Spy Who Shagged Me” — but he’s conned by a dodgy band manager named Jonny (Rupert Grint, of “Harry Potter” fame) who’s deeply in debt to some loan sharks. Jonny takes the money and produces a look-alike Kubrick, his scruffy hippie roommate Leon (Robert Sheehan, who comes across as the poor man’s Russell Brand).