Directed by Robert Zemeckis

Produced by Bob Gale & Neil Canton

Written by Robert Zemeckis & Bob Gale

Starring Michael J. Fox & Christopher Lloyd

Music by Alan Silvestri

The Back to the Future franchise is a comedic science fiction adventure film series written by Bob Gale and Robert Zemeckis, directed by Zemeckis, produced by Amblin Entertainment, and distributed by Universal Pictures. Starting with Back to the Future, the films follow the adventures of a high school student, Marty McFly (Michael J. Fox), and an eccentric scientist, Dr. Emmett L. Brown (Christopher Lloyd), as they use a DeLorean time machine to time travel to different periods in the history of Hill Valley, California.

The first film was the highest-grossing film of 1985 and became an international phenomenon, leading to the second and third films which were back to back film productions, released in 1989 and 1990, respectively. Though the two sequels did not perform quite as well at the box office as the first film, the trilogy remains immensely popular after a quarter of a century and has yielded such spin-offs as an animated television series and a motion-simulation ride at the Universal Studios Theme Parks in Universal City, California; Orlando, Florida (now closed), and Osaka, Japan, as well as a Microsoft Windows, Macintosh, iPad, PS3 and Wii video game. The film's visual effects were done by Industrial Light and Magic. All together, the trilogy was nominated for five Academy Awards, winning one (Best Sound Editing).

Back to the Future (1985)

Seventeen year old Marty McFly is accidentally sent back in time from 1985 to 1955 in a time machine built from a DeLorean by eccentric scientist Emmett "Doc" Brown, when attacked by Libyans from whom Brown stole the plutonium which gives the flux capacitor the 1.21 gigawatts needed for time travel. Upon arriving in 1955, Marty inadvertently causes his mother Lorraine to fall in love with him, rather than with his father George McFly, beginning a paradox that would cause Marty to disappear from existence. With no additional plutonium to power the time machine, Marty must find the 1955 version of Doc Brown to help him reunite his parents and return to 1985. The efforts of Biff Tannen, George's bully and future employer, further complicates Marty's situation, until Marty successfully causes his parents to fall in love and simultaneously convinces George to finally stand up to Biff. Returning to the future via a 1.21 gigawatt lightning strike that jumpstarts the machine, Marty discovers a vastly improved future for the McFly family, as Biff is now their auto detailer rather than George's boss. Despite Doc's insistence on not knowing details of the future, a note Marty leaves in his pocket in the past saves him from being killed by the terrorists. However, in the film's final moments, Doc Brown appears in a modified version of the Delorean, and tells Marty that he must travel to the future to undo some situation caused by Marty's kids.

Back to the Future Part II (1989)

The series continues as Doc Brown travels with Marty to the year 2015 where he has discovered Marty's family is in ruins. Marty buys a sports almanac containing the outcomes of 50 years worth (1950–2000) of sporting events. However, Doc catches him and throws the almanac in the trash, where the aged Biff Tannen finds it. While Marty and Doc are at Marty's future house, Old Biff steals the DeLorean time machine and gives the book to his younger self just before he goes to the dance at the end of the first movie. When Doc and Marty return to 1985, they find that Biff has used the almanac's knowledge for financial gain, which allows him to turn Courthouse Square into a 27 story casino, take over Hill Valley, get away with the murder of Marty's father, and later marry Marty's mother. Marty learns that Biff was given the book by old Biff on November 12, 1955, so he and Doc go back to that date in order to steal the almanac from Biff before he can use it to destroy their lives. They accomplish this in a complex fashion, often crossing their own past-selves' paths. When the duo are about to travel back to 1985, a lightning bolt strikes the DeLorean and activates the time circuits, sending Doc back to 1885 and leaving Marty stranded once again in 1955.

Back to the Future Part III (1990)

After finding out that Doc Brown is trapped in 1885, Marty sets out to find the 1955 Doc to help him fix the DeLorean (which has been waiting for him in a mineshaft for 70 years) and restore it to working order. Learning that Doc gets shot in 1885 by Biff's Great-Grandfather, Buford "Mad Dog" Tannen, Marty travels back in time to save Doc (who has become a blacksmith) and bring him back to the future. Unfortunately, an arrow has ripped a hole in the fuel line, emptying the gas tank and rendering the DeLorean engine useless. Furthermore, Doc falls in love with schoolteacher Clara Clayton, and considers staying in 1885. Marty must convince Doc to come back with him and find a way to get back to his time before it's too late. After several dramatic action scenes involving a speeding locomotive, Marty returns to 1985 in the restored DeLorean. It appears on a train track as planned, and Marty jumps out just in time to see the DeLorean time machine destroyed by a modern train. He worries that Doc has been lost in the past forever, when suddenly Doc Brown appears in a new time machine, modeled after a locomotive. He introduces Marty to Clara (to whom he is now married) and his two sons, Jules and Verne. When Marty asks if Doc and his family are going to the future, Doc replies that he's "already been there." The locomotive flies across the sky and disappears, ending the trilogy.