Quentin Tarantino’s new movie, Once Upon a Time in Hollywood is about to premiere at the Cannes Film Festival. And Tarantino kind of doesn’t want people to talk about it.

Or at least he wants them to be extremely careful. Tarantino published a letter to the public on the Once Upon a Time in Hollywood Twitter account today, asking people not to spoil his movie for those of us who aren’t currently sunning in the south of France. It reads in part:

I’m thrilled to be here in Cannes to share Once Upon a Time... In Hollywood with the [Cannes] festival audience. The cast and crew have worked so hard to create something original, and I only ask that everyone avoids revealing anything that would prevent later audiences from experiencing the film in the same way.

It’s really hard to judge how easy or how difficult it is to “spoil” a movie without watching it first. We already know Once Upon a Time in Hollywood is at least based in part on the Manson Family murders. Those are a matter of public record and it’s hardly a spoiler to say what happens to the Family’s victims, even if their victims happen to be major characters in the film. On the other hand, Tarantino’s made movies based on history before, and then strayed wildly from the actual events — as in Inglourious Basterds, when he gave Adolph Hitler a, shall we say, fictional demise. So even knowing the Manson story, you might not know what happens in this movie.

Still, if you don’t want people to know what happens in your movie — a desire I can absolutely understand — it might not be the wisest thing to premiere it several months early at the most important film festival in in the world in front of the assembled world press. I guess we’ll see how well they honor his request. Once Upon a Time in Hollywood opens in theaters on July 26. Here’s Tarantino’s Twitter letter.

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