Lifeforce is a 1985 science fiction film directed by Tobe Hooper and written by Dan O’Bannon and Don Jakoby, based on Colin Wilson’s 1976 novel, The Space Vampires. Featuring Steve Railsback, Peter Firth, Frank Finlay, Mathilda May, and Patrick Stewart, the film portrays the events that unfold “after a trio of humanoids in a state of suspended animation are brought to earth after being discovered in the hold of an abandoned European space shuttle.”
As the film opens a joint US-UK crew on board the nuclear-powered space shuttle Churchill is on a mission to investigate Halley’s Comet under the command of US Air Force Colonel Thomas Wolfe Carlsen (Railsback). They find a 150-mile long alien spaceship hidden in the comet’s corona, seemingly derelict. Upon entering the spacecraft, the crew finds hundreds of dead, shrivelled bat-like creatures and three naked humanoid bodies (two male and one female) in suspended animation within glass containers. The crew recovers the three aliens and begins the return trip to Earth.
During the return journey, Mission Control loses contact with the shuttle and a rescue mission is launched to investigate. The rescuers discover that the Churchill has been severely damaged by fire, with its internal components (including video) destroyed, and the three containers bearing the aliens are all that remain intact. The aliens are taken to the European Space Research Centre in London where they are watched over by Dr. Leonard Bukovsky (Gothard) and Dr. Hans Fallada (Finlay).
Prior to an autopsy, the female alien (May), referred to throughout the film as the Space Girl, awakens and fully drains the “life force” out of a guard, as well as some extra energy from the intervening Bukovsky. The Space Girl then escapes the research facility and proceeds to drain various other humans of their life force, revealing in the interim an ability to shape-shift.
It transpires that the aliens are in fact part of a race of space vampires that consume the life force of living beings, rather than their blood. To make matters worse, their victims, which are in a mummified state when completely drained, are temporarily revived as zombies that are also capable of draining others of their life forces, each victim needing a regular infusion of life energy every two hours lest they disintegrate or explode into clouds of ash…