How many movies began their existence as an April Fools’ joke? As of today, at least one.

That would be the upcoming Sadako Versus Kayako. Sadako is the creepy ghost girl from The Ring franchise. Kayako is the ghost from The Grudge series. Per Variety, a Freddy Versus Jason-style rumble between the two was initially conceived only as an April Fools’ Day prank. But when the joke went viral, producers said “Wait a second. Why are we making fun of this dopey idea when we could profit off this dopey idea?” And in that second, a new crossover sequel franchise was born. The film is being produced by Kadokawa and NBCUniversal Japan, and is already set for a June 2016 release. It’s being directed by Koji Shiraishi (Grotesque); that’s the first teaser above there (via Bloody Disgusting).

If the movie makes its way to our shores, either in its original form, or as some kind of American remake, it would be the latest step in an uptick in J-horror on these shores. (We’re already getting a new sequel/version/whatever of The Ring, called Rings, and due on April 1.) Sadako Versus Kayako also suggests that, regardless of genre, the next big thing in franchises is combinations and fights between beloved characters. Batman and Superman tussle next spring; Captain America and Iron square off a few months later. In a couple years, we’ll see a big battle between King Kong and another Japanese icon, Godzilla. If any of these movies score at the box office, expect plenty more variations in the future.

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