Set in L.A. in the near future, society is falling apart, with the rich getting richer and the poor getting progressively poorer. Drifter John Nada (played by former wrestler Roddy Piper) wanders into town looking for work. Finding a job on a building site, he befriends a worker named Frank (Keith David), who shows him to a homeless camp, where he can stay. Although John soon realises there's more to the place than meets the eye.
The first sign of things being amiss is when they pick up a hacking broadcast on their TV, saying that they have been invaded and the world is an optical illusion. The next thing he see's is that the shelter organisers are planning some sort of terrorist attack. Somewhat bemused, he doesn't get much time to reflect on these events, as the police turn up and bulldoze the camp, gunning down it's organisers in the process.
Then things really get bizarre when John discovers a box of designer sunglasses in the rubble of the shelter. After trying a pair on, he suddenly realises that the world is indeed not as it seems, as whilst looking through them he can see Spaceships passing overhead, advertisements displaying subliminal messages, and half the people in the street are in fact bug eyed aliens.
He soon finds himself on the run with his friend Frank, after shooting up a bank full of aliens, and the authorities come after him. Leading to a massive pitched battle in the aliens main headquarters, as they try and shut down the signal generator that prevents people from seeing the aliens.
Originally panned by critics and released direct-to-video here in the UK, it went on to become something of a cult classic amongst John Carpenter fans, and those who enjoy the horror/sci-fi genre. Overall I thoroughly enjoyed this, so if you like sci-fi action thrillers I would strongly suggest seeking this out.