'Apollo 18' Trailer Premieres Online

'Cloverfield'-style found-footage flick posits aliens are reason man hasn't been back to moon.

Everybody knows that man last set foot on the moon in 1972. The brand-new trailer for "Apollo 18," which premiered Friday on Apple.com, asks the question: "Why haven't we been back?"

From director Gonzalo Lopez-Gallego and producer Timur Bekmambetov, the trailer for "Apollo 18" mixes what appears to be archival footage of early space shuttle launches with "Paranormal Activity" -style "found footage" of a secret 1973 mission to the lunar surface, supposedly kept hidden from the public because of what the astronauts discovered.

"In the years following [Apollo 17] there was unconfirmed intelligence of an 18th mission," the trailer reads. "No evidence has ever been found. Until now."

Although not made explicit, the "Cloverfield" -style flick showcases several alarming incidents in its trailer, including a number of shots where it's clear the astronauts are not alone on the seemingly barren and deserted satellite. One particularly jarring shot shows one of the astronauts infected to the point of possession; another shows several non-human footprints in the gray lunar dust.

Conspiracy theories aside, and depending on your perspective, there actually was an Apollo 18 mission. Launched in 1975, the Apollo-Soyuz Test Project was a joint mission between US and Russian forces, officially and symbolically ending the great space race of the preceding decade.

The alternate history story is the English language debut of Spanish auteur Lopez-Gallego. Released by Dimension Films, "Apollo 18" will hit theaters April 22.

Check out everything we've got on "Apollo 18."

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