Alien Resurrection is a 1997 American science-fiction action horror film directed by Jean-Pierre Jeunet and written by Joss Whedon. It is the fourth installment in the Alien film series, and the final installment in the original series. It was filmed at the 20th Century Fox studios in Los Angeles, California.
The film stars Sigourney Weaver reprising her role as Ellen Ripley. Set 200 years after the preceding installment Alien 3 (1992), Ripley 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. Tom Woodruff, Jr. plays the Alien Queen, and the Newborn. Additional roles are played by Winona Ryder, Ron Perlman, Dan Hedaya, J. E. Freeman, Brad Dourif, and Michael Wincott.
Alien Resurrection was released on November 26, 1997, and received mixed reviews from film critics. Roger Ebert of the Chicago Sun-Times felt "there is not a single shot in the movie to fill one with wonder", later naming it one of the worst films of 1997,  while Desson Thomson of The Washington Post said the film "satisfactorily recycles the great surprises that made the first movie so powerful". The film grossed $47.7 million in North America, the least successful of the Alien series on that continent. It was well received internationally, however, with a gross of $113.5 million, bringing its total gross to $161.2 million. It was the 43rd highest-grossing film in North America in 1997, four days after Anastasia, another 20th Century Fox film.  The film was nominated for six Saturn Awards (including Best Science Fiction Film, Best Actress for Weaver, Best Supporting Actress for Ryder, and Best Direction for Jeunet).
A sequel to Resurrection was planned as Joss Whedon had written an earth-set script for Alien 5, though Sigourney Weaver was not interested in this setting, but has remained open to reprise her role as Ellen Ripley for a fifth installment on the condition that she likes the story. Although more sequels were planned to follow Resurrection, the series became a prequel series with the 2012 film Prometheus directed by Ridley Scott, who stated that the film precedes the story of Alien, but is not directly connected to the original film's franchise, and that Prometheus explores its own mythology and ideas.
In 2379, two hundred years after the events of Alien 3, military scientists on the space vessel USM Auriga create a clone of Ellen Ripley, designated Ripley 8, using DNA from blood samples taken before her death. The xenomorph queen's DNA has been mixed in with Ripley's, and the clone grows up with an embryo inside it. The scientists extract the embryo, raise it and collect its eggs while keeping Ripley 8 alive for further study. As a result of the xenomorphs' DNA inside her, she has enhanced strength and reflexes, blood that is somewhat acidic and a psychic link with the xenomorphs. Additionally, the xenomorph's genetic memory allows the clone to have some of Ripley's memories.
A group of mercenaries, Frank Elgyn, Johner, Christie, John Vriess (who constantly whistles "I'm Popeye the Sailor Man"), Sabra Hillard and Annalee Call, arrive at Auriga on their ship Betty. They deliver several kidnapped humans in stasis. The military scientists use the humans as hosts for the Aliens, raising several adult Aliens for study.
The Betty crew soon encounters Ripley 8. Call recognizes her name and tries to kill her, suspecting she may be used to create xenomorphs, but is unaware the creatures have already been cloned. The xenomorphs, having matured, escape confinement by killing off one of their own to use their acidic blood to burn through their enclosures, aware of their blood's acidity from said genetic memory. They then capture Dr. Jonathan Gediman and kill a second scientist. They damage the Auriga and kill some of those people who do not evacuate, including General Perez and Elgyn. Another crew member is cocooned for eggmorphing. Military scientist Dr. Wren reveals that the ship's default command in an emergency is to return to Earth. Realizing this will unleash the xenomorphs on Earth, Ripley 8, the mercenaries, Wren, a Marine named DiStephano and a surviving xenomorph host, Purvis, decide to head for the Betty and use it to destroy the Auriga. Along the way, Ripley 8 discovers a laboratory which contains the grotesque results of the previous seven failed attempts to clone Ellen Ripley. The surviving one begs Ripley 8 to euthanise her; she complies and then incinerates the lab and its contents.
As the group makes their way through the damaged ship, they swim through a flooded kitchen. They are chased by two xenomorphs. One is killed, while the other snatches Hillard. As they escape the kitchen, the xenomorph returns and blinds Christie, who sacrifices himself to kill the xenomorph so the others can escape. After Wren betrays the group, Call is revealed to be an auton, an improved version of a human created by synthetics. Using her ability to interface with the Auriga's systems, Call sets it on a collision course with Earth, hoping to destroy the xenomorphs in the crash. She cuts off Wren's escape route and directs the xenomorphs towards him. Ripley 8 is captured by a xenomorph, while the others head for the Betty. Wren, who is already aboard, shoots Purvis, takes Call hostage and demands that she abort the collision. An injured Purvis attacks Wren and forces Wren's head to his chest just as the xenomorph embryo he is carrying bursts through his ribcage, causing it to go through Wren's head too, killing them both. The survivors shoot and kill the juvenile xenomorph.
Ripley is taken to the Alien nest, where she finds Gediman, still alive and partially cocooned. The xenomorph queen, having developed a uterus as a result of her genetic contamination with Ripley 8, gives birth to a xenomorph with overtly human traits. The hybrid xenomorph recognizes Ripley 8 as its mother, killing the queen and Gediman. Ripley 8 takes advantage of the distraction to escape, and makes her way to the Betty.
The "newborn" reaches the Betty and attacks Call, killing DiStephano when he tries to help her. Ripley 8 finds her way onto the ship and saves Call by distracting the hybrid. Using her acidic blood, Ripley 8 melts a hole in a window and pushes the hybrid towards it. The decompression violently sucks the creature through the hole and out into space, killing it as Ripley 8 tearfully watches on.
The countdown on the Auriga continues as the survivors escape in the Betty. The Auriga collides with Earth, causing a large explosion. As they look down at Earth, Call asks what Ripley 8 wants to do next. "I'm a stranger here myself," she replies. In an alternate ending that appears in some versions, the Betty lands in a ruined Paris.
- Sigourney Weaver as Ellen Ripley Clone 8, reprising her role from the previous three Alien films. After having sacrificed herself to kill the Alien Queen gestating inside her in Alien 3, Ripley has been cloned using blood samples so that the military may extract the Queen embryo. As a result of the cloning process Ripley has been affected by the Alien queen's DNA. She has enhanced strength and reflexes, acidic blood, and can sense the presence of the Aliens. Weaver also portrayed the failed Ellen Ripley Clone 7.
- Nicole Fellows as Young Ripley
- Winona Ryder as Annalee Call, the newest crew member of the Betty. She recognizes Ripley and has knowledge of the Aliens. Call is revealed during the course of the film to be a synthetic and helps the surviving crew interface with the Auriga.
- Michael Wincott as Frank Elgyn, captain of the mercenary ship Betty. Elgyn brings the Betty to the Auriga in order to sell kidnapped humans in cryostasis to General Perez. He is romantically involved with Hillard.
- Dan Hedaya as General Martin Perez. Perez is the commanding officer of the Auriga and supervises the experiments to clone Ripley and study the Aliens.
- J. E. Freeman as Dr. Mason Wren. Wren is one of several scientists aboard the Auriga involved in cloning Ripley and studying the Aliens. After the Aliens escape he joins the lead characters in their attempt to flee the ship.
- Brad Dourif as Dr. Jonathan Gediman, another of the scientists involved in cloning Ripley and studying the Aliens. One alien attacks him after he tries to chase them.
- Marlene Bush as Dr. Carlyn Williamson, the third member of the science team responsible for cloning Ripley. She is often confused with another female scientist in the film (Carolyn Campbell) as the two look strikingly similar.
- Carolyn Campbell as Unnamed Scientist.
- David St. James as Dr. Dan Sprague, another member of the Auriga's science team.
- Raymond Cruz as Vincent Distephano. Distephano is a soldier stationed aboard the Auriga. When the Aliens break out, he joins the crew in their attempt to escape from the ship.
- Kim Flowers as Sabra Hillard, the assistant pilot of the Betty who is romantically involved with Elgyn.
- Gary Dourdan as Christie, the first mate and second in command of the Betty.
- Ron Perlman as Johner, a mercenary and member of the Betty's crew. Johner makes bad jokes, has a short temper, and teases Vriess about his handicap.
- Dominique Pinon as John Vriess, the Betty's mechanic. A paraplegic, he uses a motorized wheelchair. Vriess shares a close friendship with Call and an antagonistic relationship with Johner.
- Leland Orser as Larry Purvis. Purvis is one of several humans who have been kidnapped by the crew of the Betty while in cryosleep and delivered to the Auriga to serve as hosts for the Aliens. Despite having an Alien growing inside him, Purvis joins the surviving crew in an attempt to escape from the Auriga.
- Tom Woodruff, Jr. as the lead Alien, Alien Queen, and the Newborn. Woodruff had previously played the Alien in Alien 3, and described the Alien in Resurrection as feeling "much more like a dog. It's got dog legs, a more pointed nose, and a more vicious mouth." Weaver praised Woodruff's work, saying that "working with him is like working with Lon Chaney, only Tom's usually covered with K-Y Jelly." Woodruff also played the lead Alien in the crossover films, Alien vs. Predator and Aliens vs. Predator: Requiem.
- Joan LaBarbara as The Newborn (voice)
- Archie Hahn as The Newborn (voice)
- Garrett House as Olsen. A soldier.
- Daniel Raymont as Vehrenberg. A soldier.
- David Rowe as Brian Clauss. A frozen soldier.
- Steven Gilborn as Father (voice). The artificial intelligence system of the USM Auriga.