They Live

Drifter "John Nada" finds construction work in Los Angeles and befriends fellow construction worker Frank Armitage, who leads him to a shanty town soup kitchen. A disruptive television signal and a preacher both warn of conspiracies, and Nada discovers a nearby church is a front for scientific equipment. After the church is raided and the shantytown bulldozed, Nada retrieves a box of sunglasses from the church's wall, wearing one pair and hiding the rest in an alley dumpster. The sunglasses reveal a hidden reality: media and advertising hide omnipresent subliminal stimuli to obey, consume, reproduce, and conform, while many of the elite are actually humanoid aliens. Read more on Wikipedia.