In the film, which is set 200 years after the preceding installment Alien 3 (1992), Ellen Ripley (Sigourney Weaver) is cloned and an Alien queen is surgically removed from her body. The United Systems Military hopes to breed Aliens to study and research on the spaceship USM Auriga, using human hosts kidnapped and delivered to them by a group of mercenaries. The Aliens escape their enclosures, while Ripley and the mercenaries attempt to escape and destroy the Auriga before it reaches its destination, Earth.

Alien: Resurrection was released on November 26, 1997 and received mixed reviews from film critics. Whedon's initial screenplay had a third act on Earth, with a final battle for Earth itself. Whedon wrote five versions of the final act, none of which ended up in the film. Weaver was impressed with Whedon's script. She thought that the error during Ripley's cloning process would allow her to further explore the character, since Ripley becoming part human and part Alien would create uncertainty about where her loyalties lay. This was an interesting concept to Weaver, who thought the film brought back the spirit of Alien and Aliens. Weaver received a co-producer credit and was reportedly paid $11 million.

Special effects company Amalgamated Dynamics Incorporated (ADI) was hired for the film, having previously worked on Alien 3. ADI founders Tom Woodruff, Jr. and Alec Gillis also had experience working with Stan Winston on Aliens. ADI based their designs and modifications of the Alien creatures on the film's script, which included the creatures having pointed tails for swimming, making their head domes and chins more pointed, and establishing them to appear more vicious using techniques of camera angles and shot duration. After receiving the director's approval, ADI began to create small sculptures, sketches, paintings, and life-size models.