Much of the 1969 Los Angeles seen in Quentin Tarantino’s new film Once Upon a Time in Hollywood is real, but you could be forgiven for thinking otherwise. The film’s characters, like most Los Angelenos, spend a lot of time driving from place to place. Their travels find them floating along to mostly forgotten versions of famous songs while they pass theaters with marquees promoting movies possibly no one but Tarantino has thought about for years. The 1969 we now remember — with its political upheaval, Moon landing, and game-changing films like Easy Rider — mostly exists outside of this world. This is a 1969 LA in which José Feliciano sings “California Dreamin’” and ads promote an intriguing new sex comedy called 3 in the Attic, both of which are vaporous bits of pop culture that have since faded into hazy memory. There’s a lot going on in Tarantino’s latest film, including an exploration of the delicacy of a moment in time and how easily an era can be swept away.

The one landmark 1969 event the film does depict — at least, sort of — only reinforces that notion. On the night of August 8th, 1969, three members of the Manson family committed mass murder at the home of Roman Polanski (who was out of town working on a movie at the time) and Sharon Tate (who was among the victims). Joan Didion famously signposted the murders as the symbolic end of the 1960s, and they serve that purpose well. Yet, despite the major role that the Manson family plays in the film (this review will do its best to keep that and other major plot elements unspoiled), Once Upon a Time in Hollywood is very much a film about the moments before an era comes to an end and the people who live in that era, including their joys, frustrations, and inability to see what’s coming around the corner.

When the film opens, frustrations have long since overtaken joy for Rick Dalton (Leonardo DiCaprio). He saw considerable success as the star of the Western TV series Bounty Law in the early ’60s, but he hasn’t quite figured out how to roll with the times. His film career has never taken off, and while he doesn’t want for work, that mostly means putting in guest spots as bad guys on shows helmed by younger up-and-coming stars. He drinks too much and worries even more, as one habit feeds into the other in a self-destructive cycle. But Dalton also knows he can still act, given the right surroundings. He’s forced to consider a change of scenery after a meeting with Marvin Schwarz (Al Pacino), a Hollywood agent who wants to send him to Rome to star in Westerns, which is a move Rick really doesn’t want to make.

Counseling him through this crisis — and driving him, since Dalton’s license has been suspended — is Cliff Booth (Brad Pitt), Dalton’s longtime stuntman who now mostly helps out his old boss by doing odd jobs, running errands, and, above all, lending moral support. Cliff has a dubious past and sometimes exercises questionable judgment, which are qualities that have cut into his own professional prospects. But Cliff doesn’t seem to mind all that much. He believes in Rick and seems perfectly happy doing his chores when not hanging out in the trailer he shares with an obedient and extremely hungry pit bull behind a drive-in theater in Van Nuys.

This allows him to spend time cruising, where he meets all kinds of intriguing characters, including Pussycat (Margaret Qualley), a teenage hippie whom he eventually learns is staying at the old Spahn Movie Ranch with a bunch of followers of someone named Charlie. But Cliff has no way of making a connection between this Charlie and the odd-looking fellow he witnessed showing up at the home of Rick’s neighbor, Sharon Tate (Margot Robbie), or knowing that Sharon’s experiencing a less-pronounced version of the same career ennui that’s troubling Rick.

That’s the basic setup of a movie that’s more about the setup than a traditional plot. Tarantino coined the term “hang-out movie” to describe the tradition to which he felt Jackie Brown belonged, films in which spending time with appealing, memorable characters mattered more than what happened to those characters. He also cited his favorite film, Howard Hawks’ Rio Bravo, as the beau ideal of such a movie. If anything, even less happens in Hollywood than most hang-out movies. The presence of the Manson family points toward an endpoint for the story, but the stretches leading up to that moment are less about pushing a narrative forward and more about observing the main characters at telling moments: Rick guest stars on the pilot of the (real) TV show Lancer. Cliff takes a hitchhiker to Spahn Ranch and observes how much its new residents have changed it. Sharon spends an afternoon alone at the movies.

All the while, the film uses a scrupulous production design to create the illusion of time travel. Tarantino, as usual, draws on several sources. In this crucial respect, it most resembles Mike Mills’ 20th Century Women, his memory-driven revisiting of the late 1970s. Though it’s less directly autobiographical, Once Upon a Time in Hollywood feels similarly personal, like an attempt to re-create the world Tarantino glimpsed as a kid growing up in Los Angeles and, in the process, maybe better understanding that moment and capturing what was lost in August 1969. This happens on a personal level — Robbie’s warm, openhearted performance as Tate helps humanize a woman who will be forever known as a murder victim — and a cultural level.

It’s also an attempt to understand those who lived there. First seen drawling and stuttering as he nervously awaits a meeting that could change his life, Rick is a fascinatingly contradictory character. He has an outsized ego and an outsized vulnerability to match. He tries to avoid work he feels is beneath him, while desperately clinging to what he’s earned before it slips away. DiCaprio beautifully captures that swirl of emotions and the ways they can spin out of control. Rick talks and smokes and rarely sits still. It’s a stark contrast to Cliff, who says as little as possible and seems happy to drift through life. But it also alludes to darkness in his past and trails even darker rumors behind him. Cliff is on-screen through much of the film, and he exits as much of a mystery as he enters.

There’s one thing that is knowable about Cliff: he loves Rick, and Rick loves him. Their bond, though occasionally put under stress, forms the heart of this surprisingly warm movie. Tarantino doesn’t short audiences on the expected technical bravado, memorable dialogue, or flashes of violence — see an early scene following Cliff home that finds a camera flying above a drive-in screen and a long scene between Rick and a precocious child actor (Julia Butters) for examples. But in Once Upon a Time in Hollywood, none of that matters as much as the central friendship, an unlikely partnership that could only have happened in a moment long lost. Here, it’s summoned and returned as a place we’re invited to visit with the bittersweet understanding that our stay, like the era it depicts, must eventually end.