THEY LIVE!

Nada, a down-on-his-luck construction worker, discovers a pair of special sunglasses. Wearing them, he is able to see the world as it really is: people being bombarded by media and government with messages like "Stay Asleep", "No Imagination", "Submit to Authority". Even scarier is that he is able to see that some usually normal-looking people are in fact ugly aliens in charge of the massive campaign to keep humans subdued.




TRIVIA
The line "I have come here to chew bubble gum and kick ass, and I'm all out of bubble gum" was ad-libbed by Roddy Piper. According to director John Carpenter, Piper had taken the line from a list of ideas he had for his pro wrestling interviews.

The credited writer "Frank Armitage" is a reference to a character in Lovecraft's "The Dunwich Horror." Director John Carpenter stated in an interview he agreed with many of Lovecraft's world views, which helped shape the film's direction.

Writer "Frank Armitage" is actually director John Carpenter.

The fight between Nada (Roddy Piper) and Frank (Keith David) was only supposed to last 20 seconds, but Piper and David decided to fight it out for real, only faking the hits to the face and groin. They rehearsed the fight for three weeks. Carpenter was so impressed he kept the 5 minute and 20 second scene intact.

The communicators that the guards use are the P.K.E. meters from Ghost Busters (1984).

Roddy Piper's character never gives his name nor is he referred to by name throughout the entire movie. He is simply referred to as "Nada" in the credits, which means "nothing" in Spanish.

There is a thinly veiled jab at "Siskel & Ebert & the Movies" (1986), with both Gene Siskel and Roger Ebert as aliens. "Siskel" is denouncing George A. Romero and John Carpenter as too violent. (In fact, Siskel had written a scathing review of Romero's Night of the Living Dead (1968).)

The only character given a first and last name is Holly Thompson (Meg Foster).

John Carpenter wanted a truly rugged individual to play Nada. He cast wrestler Roddy Piper in lead role after seeing him at _Wrestlemania III (1987) (V)_ . Carpenter remembered Keith David's performance in The Thing (1982) and wrote the role of Frank specifically for the actor.

The main character is listed in the credits as being named "Nada." This is most likely a reference to George Nada, the main character of Ray Nelson's short story "Eight O'Clock in the Morning," which was the basis for ‘They Live’.

More info from IMDB