The Rocky Horror Picture Show is a 1975 independent musical comedy horror film produced by Lou Adler and Michael White, directed by Jim Sharman, and distributed by 20th Century Fox (later 20th Century Studios). The screenplay was written by Sharman and Richard O'Brien, who also played the supporting role Riff Raff. The film is based on the 1973 musical stage production The Rocky Horror Show, with music, book, and lyrics by O'Brien. The production is a tribute to the science fiction and horror B movies of the 1930s through to the early 1960s. The film stars Tim Curry in his debut, Susan Sarandon, and Barry Bostwick. The film is narrated by Charles Gray, with cast members from the original Royal Court Theatre, Roxy Theatre, and Belasco Theatre productions, including Nell Campbell and Patricia Quinn.

The story centres on a young engaged couple whose car breaks down in the rain near a castle, where they search for help. The castle is occupied by strangers in elaborate costumes holding a party. They then meet the head of the house, Dr. Frank-N-Furter, an apparently mad scientist and alien transvestite from the planet Transsexual in the galaxy of Transylvania, who creates a living muscle man named Rocky.

The film was shot in the United Kingdom at Bray Studios and on location at Oakley Court, a country house best known for its earlier use by Hammer Film Productions. A number of props and set pieces were reused from the Hammer horror films. Although the film is both a parody of and tribute to many kitsch science fiction and horror films, costume designer Sue Blane conducted no research for her designs. Blane has claimed that her creations for the film directly affected the development of punk rock fashion trends, such as torn fishnet stockings and colourfully dyed hair.

Initial reception was extremely negative, but it soon became a hit as a midnight movie, when audiences began participating with the film at the Waverly Theater in New York City in 1976. Audience members returned to the cinemas frequently and talked back to the screen and began dressing as the characters, spawning similar performance groups across the United States. At almost the same time, fans in costume began performing alongside the film. This "shadow cast" mimed the actions on screen, above and behind them, while lip-synching their characters' lines.

Still in limited release in 2025, 50 years after its premiere, it is the longest-running theatrical release in film history. In many cities, live amateur shadow-casts act out the film as it is being shown and heavily draw upon a tradition of audience participation. The film is most often shown close to Halloween. Today, the film has a large international cult following and has been considered by many as one of the greatest musical films of all time. In 2005, it was selected for preservation in the United States National Film Registry by the Library of Congress as being "culturally, historically, or aesthetically significant."

The film begins with a pair of floating disembodied lips welcoming the audience to a science fiction double feature ("Science Fiction/Double Feature"). Throughout the film, a criminologist from an unspecified point in the future narrates and provides commentary on the events.

Following the wedding of their friends, a naïve young couple, Brad Majors and Janet Weiss, get engaged and decide to celebrate with their high school science teacher Dr. Scott, who taught the class where they first met ("Dammit Janet"). En route to Scott's house on a dark and rainy night, they get lost and suffer a flat tyre. Seeking a telephone to call for help, the couple walks to a nearby castle ("Over at the Frankenstein Place") where a party is being held. They are accepted in by the strangely dressed inhabitants, led by the butler Riff Raff, the maid Magenta, and a groupie named Columbia, who dance to "The Time Warp". Dr. Frank-N-Furter, a transvestite mad scientist, introduces himself and invites them to stay for the night ("Sweet Transvestite").

With the help of Riff Raff, Frank brings to life a tall, muscular, handsome blond man named Rocky ("The Sword of Damocles"). As Frank vows he can improve Rocky into an ideal man in a week ("I Can Make You a Man"), Eddie, a motorcyclist with a bandaged head, breaks out of a deep freeze ("Hot Patootie – Bless My Soul"). Frank kills Eddie with an ice axe, justifying it as a "mercy killing". Rocky and Frank depart for the bridal suite ("I Can Make You a Man (Reprise)").