| Director | Roger Christian |
|---|---|
| Budget | $44 million |
| Box office | $29.7 million |
In 3000 AD, Jonnie Goodboy Tyler lives in the Rocky Mountains with a band of cave-dwellers who fear the "demons" that rule Earth. Jonnie doubts their stories and rides into the lowlands, where hunters Carlo and Rock show him a desolate and overgrown city. While exploring it, he is captured by the demons, a cruel alien race called Psychlos, and taken as a slave to a base in the ruins of Denver. The base is covered with an enormous dome that provides the Psychlos with a breathable atmosphere. Jonnie shows resourcefulness, drawing the respect of the other human slaves and the interest of Terl, the high-born Earth security chief.
Terl learns from a visiting supervisor that his temporary assignment on Earth will be extended indefinitely as punishment for offending a politician. Desperate to leave, he hatches a plan with his assistant Ker. They know about a recently exposed gold deposit in an area with elevated radiation levels. Gold is valuable to the Psychlos, who have been reporting losses from their mining operations, but radiation causes their air mixture to explode. Terl and Ker will train humans to mine the gold, and Terl will use part of it to bribe his way off the planet.
Terl places Jonnie in a learning machine that rapidly teaches him Psychlo language and technology. Jonnie shares his knowledge with other slaves while hiding it from Terl and Ker. After Jonnie stages an unsuccessful escape attempt, Terl takes him to the Denver Library hoping to impress him that human knowledge is no match for the Psychlos. Jonnie reads the Declaration of Independence and is inspired to seek not only escape but reconquest. Jonnie's fiancée Chrissy is captured while searching for him and fitted with an explosive collar. Terl tells Jonnie that she will be killed if he does not obey, also making an example out of a fellow slave, Sammy.
Believing that the slaves are subdued, Terl blackmails the planet administrator into letting him order the gold mining operation. Jonnie receives further training to pilot aircraft and is sent to the mining site with a team. He leaves half of them to pretend to work while the other half gather abandoned human weapons and take gold from Fort Knox to pass off as mining production. Ker tries to blackmail Terl for a greater share of the gold at Jonnie's urging, but Terl detects the attempt and shoots off Ker's hand.
The humans launch their revolt, assaulting the base while using Harrier jets to combat the Psychlo air defenses and explosives to rupture the dome. Terl orders the execution of all humans and alerts the Psychlo homeworld to teleport an extermination force. As the teleporter activates, Jonnie fights with Terl, reattaching Chrissy's collar to his arm and tricking him into detonating it. Sammy's brother Mickey rides the teleporter to the homeworld with a nuclear weapon. The fallout from the weapon incinerates the atmosphere, causing the entire planet to explode.
At Fort Knox, Jonnie gloats at a captive Terl, telling him that surviving Psychlos will pay any price for him after they learn that his scheme led to their defeat. Ker agrees to teach Psychlo technology to the humans and gloats along with them.