Star Trek: First Contact is a 1996 American science fiction film directed by Jonathan Frakes in his feature film debut. It is the eighth movie of the Star Trek franchise, and the second starring the cast of the television series Star Trek: The Next Generation. In the film, the crew of the starship USS Enterprise-E travel back in time from the 24th century to the 21st century to stop the cybernetic Borg from conquering Earth by changing the past.

After the release of Star Trek Generations in 1994, Paramount Pictures tasked writers Brannon Braga and Ronald D. Moore with developing the next film in the series. Braga and Moore wanted to feature the Borg in the plot, while producer Rick Berman wanted a story involving time travel. The writers combined the two ideas; they initially set the film in Renaissance Italy, but changed the time period that the Borg corrupted to the mid-21st century, after fearing the Renaissance idea would feel kitschy. After two better-known directors turned down the job, cast member Jonathan Frakes was chosen to direct to make sure the task fell to someone who understood Star Trek.

The film's script required the creation of new starship designs, including a new USS Enterprise. Production designer Herman Zimmerman and illustrator John Eaves collaborated to make a sleeker ship than its predecessor. Principal photography began with weeks of location shooting in Arizona and California, before production moved to new sets for the ship-based scenes. The Borg were redesigned to appear as though they were converted into machine beings from the inside-out; the new makeup sessions took four times as long as their appearances on the television series. Effects company Industrial Light & Magic rushed to complete the film's special effects in less than five months. Traditional optical effects techniques were supplemented with computer-generated imagery. Jerry Goldsmith composed the film's score.

Star Trek: First Contact was released on November 22, 1996, and was the highest-grossing film on its opening weekend. It grossed a worldwide total of $146 million. Critical reception was mostly positive; critics including Roger Ebert considered it to be one of the best Star Trek films. The Borg and the special effects were lauded, while characterization was less evenly received. Scholarly analysis of the film has focused on Captain Jean-Luc Picard's parallels to Herman Melville's Ahab and the nature of the Borg. First Contact was nominated for the Academy Award for Best Makeup, and won three Saturn Awards. It was followed by Star Trek: Insurrection in 1998.

In the 24th century, Captain Jean-Luc Picard awakens from a nightmare in which he relives his assimilation by the cybernetic Borg six years earlier. He is contacted by Starfleet, who inform him of a new Borg threat against Earth. Picard's orders are for his ship, USS Enterprise, to patrol the Neutral Zone in case of Romulan aggression; Starfleet is worried that Picard is too emotionally involved with the Borg to join the fight.

Learning the fleet is losing the battle, the Enterprise crew disobeys orders and heads for Earth, where a single Borg Cube ship holds its own against a group of Starfleet vessels. Enterprise arrives in time to assist the crew of USS Defiant and its commander, the Klingon Worf. Picard takes control of the fleet and directs the surviving ships to concentrate their firepower on a seemingly unimportant point on the Borg ship. The Cube launches a smaller spherical ship towards Earth before being destroyed. Enterprise pursues the sphere into a temporal vortex. As the sphere disappears, Enterprise discovers Earth has been altered—Borg now populate it. Realizing the Borg have used time travel to change the past, Enterprise follows the sphere through the vortex.

Enterprise arrives hundreds of years in the past on April 4, 2063, the day before the historic warp drive flight that leads to humanity's first encounter with alien life. The crew surmise that the Borg are trying to prevent first contact and assimilate humanity while the planet is recovering from World War III. After destroying the Borg sphere, an away team transports down to Zefram Cochrane's warp ship, Phoenix, in Bozeman, Montana. Picard has Cochrane's assistant Lily Sloane sent back to the Enterprise for medical attention. The captain returns to the ship and leaves Commander William T. Riker on Earth to make sure Phoenix's flight proceeds as planned. While in the future Cochrane is seen as a hero, in reality he built the Phoenix for financial gain and is reluctant to be the historic figure the crew describes.

A group of Borg invade Enterprise's lower decks, assimilating some of the crew and modifying the ship. Picard and a team attempt to reach engineering to disable the Borg with a corrosive gas, but are forced back; the android Data is captured in the melee. A frightened Lily corners Picard with a weapon, but he gains her trust. The two escape the Borg-infested area of the ship by creating a diversion in the holodeck. Picard, Worf, and the ship's navigator, Lieutenant Hawk, travel outside the ship in space suits to stop the Borg from using the navigational deflector to call for reinforcements, but Hawk is assimilated in the process. As the Borg assimilate more decks, Worf suggests destroying the ship, but Picard angrily calls him a coward. Lily confronts the captain and makes him realize he is acting irrationally because of his past with the Borg. Picard apologizes to Worf and orders the activation of the ship's self-destruct and evacuation of the crew to escape pods, while he stays behind to rescue Data.