Warning: SPOILERS for Once Upon a Time in Hollywood.

Once Upon a Time in Hollywood's ending surprisingly rewrites Hollywood history to give the film's main characters, the fictional Rick Dalton (Leonardo DiCaprio) and Sharon Tate (Margot Robbie), who was a real person, a happy ending. The ninth film by Quentin Tarantino is set in 1969 Los Angeles, an era when the old guard of Hollywood was fading and being supplanted by a new generation of the counterculture, psychedelics, and hippies. But the film also revolves around the real-life murder of Tate by the Charles Manson Family - which doesn't occur in Once Upon a Time in Hollywood.

Freewheelingly melding fact and fiction, Once Upon a Time in Hollywood is riddled with Tarantino's trademark flashbacks, asides to other films and TV shows (both real and fictional), and cameos by stars of the era like Steve McQueen (Damian Lewis), Bruce Lee (Mike Moh), and Roman Polanski (Rafał Zawierucha). However, the main story of the film only takes place over the course of a few days - albeit six months apart. In February 1969, Rick Dalton, a fading star of the 1950s TV Western Bounty Law, tries to reignite his career by guest-starring as the villain-of-the-week on another Western TV series called Lancer, which lands him the opportunity to work in Rome and star in Spaghetti Westerns. Meanwhile, Sharon Tate, an actress and the wife of director Roman Polanski, slips into a movie theater in Westwood and enjoys the audience's positive reaction to her starring role in the Dean Martin spy movie The Wrecking Crew.

Related: Once Upon A Time In Hollywood Cast Guide

Six months later, it's August 1969 and Dalton is returning from Rome with his best friend and stuntman Cliff Booth (Brad Pitt) and his new Italian wife (Lorenza Izzo). In Tarantino's film, Dalton and Cliff's friendship is based on the real-life camaraderie between Burt Reynolds and his stunt double Hal Needham. After a decade of working together, Dalton can no longer afford to employ Cliff so the two plan one last night of drinking before going their separate ways. Meanwhile, Tate, who is Dalton's next-door neighbor, is eight months pregnant and hosting three friends at her home while Polanski is in Europe directing a film. August 8, 1969 is the fateful night when members of the Manson Family invaded Tate's home and murdered her and her friends, which audience members who are aware of Hollywood history, anticipate with dread.

Amazingly, that isn't what occurs in Once Upon a Time in Hollywood, which definitively reveals itself to be set in an alternate timeline rather than a recreation of our history with Tarantino's fictional characters dropped in. Here's what went down instead, how it was all ingeniously set up by Tarantino, and what it all means.

The Manson Family Invades Rick Dalton's Home Instead of Sharon Tate's - And It Goes Horribly Wrong

Once Upon a Time in Hollywood Leonardo DiCaprio

On August 8th, Manson Family members Tex (Austin Butler), Susan (Mikey Madison), Linda (Maya Hawke), and Patricia (Madisen Beaty) arrived outside Tate's house to carry out Manson's orders. However, the noise their idling car made irritated Dalton, who was inebriated from drinking with Cliff and was making margaritas while Cliff was walking his pitbull Brandy. Incensed to find hippies in his neighborhood, Dalton berates them until they go away. After the Manson Family realizes they just 'met' Rick Dalton, who they grew up watching on TV, they decided to kill him and everyone who "taught [their generation] to murder" via TV and movie violence. As they march up to Dalton's house (after Cliff had returned with his dog), Linda gets cold feet, takes their car and abandons the others.

When the armed Manson Family enters Dalton's home, Cliff, who is high from smoking an acid-dipped cigarette, is amused and doesn't think they're real at first. Gradually, the would-be killers recognize Cliff from the incident at Spahn's Ranch six months prior. Cliff then sics his pitbull on Tex, who gets mauled by the dog. Cliff kills Tex while Brandy then attacks Susan, who screams bloody murder as the dog tears at her. Cliff then violently beats Patricia to death but gets caught by an errant gunshot and falls unconscious. Blinded and still screaming, Susan smashes through Dalton's patio door and falls into the pool, terrifying Rick, who was wearing headphones and was blissfully unaware of the carnage in his home. After he gets out of the pool, Dalton gets the same flamethrower he used in 14 Fists of McClusky and uses it to roast Susan until she's dead.

After the police arrive, Cliff is taken to the hospital via ambulance while Dalton stays behind. Jay Sebring, who heard the commotion from next door, meets Dalton, who then speaks to Tate through her gateway intercom and is invited to Tate's home. Dalton then meets his neighbor for the first time.

Related: Every Song In Once Upon A Time In Hollywood

Sharon Tate's Tragic History Is Rewritten In Once Upon A Time in Hollywood

once-upon-time-hollywood-robbie

It's not until the Manson Family chooses to invade Dalton's home instead of Tate's that it becomes abundantly clear that Quentin Tarantino's film takes place in an alternate reality. In actual history, on the night of August 8, 1969, Manson Family members Tex, Susan, Patricia, and Linda invaded Tate's home and murdered her, her unborn child, Sebring, and their two houseguests, Wojciech Frykowski and Abigail Folger. Manson's orders were to "totally destroy everyone in [the house], as gruesome as you can... and make it witchy" and this gruesome mass murder made Charles Manson and his cult infamous.

Related: The True Story Behind Once Upon A Time In Hollywood

However, in real life, Rick Dalton didn't live in the house just down the hill from Tate and Polanski's home. Dalton's interference as the Manson Family was scoping out the entrance to Tate's house was the divergence point that led to Susan suggesting they alter Manson's plan and kill Dalton instead, which the others agreed to (except Linda, who abandoned them). Further, Cliff and his pitbull made all of the difference since they killed Tex and Patricia. Though they had no idea Sharon Tate was the real target, Dalton and Cliff saved their neighbor's life and changed the course of history.

How "Old Hollywood" Saved Sharon Tate

Rick shoots a commercial for Hulabaloo in Once Upon a Time in Hollywood.

Once Upon a Time in Hollywood is thematically about the transition from the old Hollywood to the new. Dalton is a relic of the old studio system and he suffered from anxiety and alcoholism over whether he could still have a career in the changing film industry. For his part, Cliff was more amenable to the hippie counterculture but he, too, was old Hollywood at heart and he stuck by his best friend through thick-or-thin (especially since Cliff is widely believed to have killed his wife and Dalton was the only one who goes to bat for him and kept him employed). After they returned from Rome, Dalton and Cliff were about to sever their professional relationship and the future for both of them was uncertain.

Yet, despite Dalton adjusting his look with longer hair and sideburns to better fit in with the changing trends, it was because of Dalton being old-fashioned that he was so furious at "a bunch of hippies" appearing outside his Hollywood Hills home. Dalton prized his abode, which he owned, and its swanky location as proof that he was still a member of the Hollywood elite. By confronting the Manson Family, Rick made unwittingly made himself their target instead of Sharon, therefore Dalton's "Old Hollywood" inadvertently saved the life of Tate, who represents "New Hollywood". Meanwhile, the ever-loyal Cliff (along with his trusty pitbull) saved Dalton and his wife Francesca. As a result of "Old Hollywood" intervening against the invasion of the counterculture, Tate not only stayed alive in Once Upon a Time in Hollywood but she never even knew she was the Manson Family's original target.

Even though they were neighbors, Dalton had never met Roman Polanski (or Sharon Tate) prior to the night of August 8th. Dalton was well-aware that the famed director lived next door and he longed to get cast in one of his films, which he felt would jumpstart his stalled movie career. By the end of Once Upon a Time in Hollywood, Rick Dalton getting to work with Roman Polanski and joining New Hollywood became a real possibility.

Next: Does Once Upon A Time In Hollywood Have An After-Credits Scene?

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