Christopher Nolan might just be the most bankable Hollywood director this side of James Cameron. Whether shepherding the most successful comic book franchise DC has ever seen or trying his hand at dizzyingly high-concept original projects, Nolan has always met with a monster windfall at the box office. It’s almost as if his films never go out of style. That’s supposed to be a joke about the song Taylor Swift wrote about Harry Styles. Who is in Christopher Nolan‘s new movie. This is very clearly not my wheelhouse, so let’s just push right ahead as if that never happened.

The English singer-songwriter and former member of boy band One Direction will star in Dunkirk, Nolan’s massively scaled reenactment of the Allied forces’ mission to escape with their lives from the Axis-surrounded Dunkirk Beach during World War II. And in a new interview with the Los Angeles Times, the filmmaker spoke a bit about the laborious process of finding just the right face for Styles’ role:

When we put the cast together, we had some established names. But for the guys on the beach, we really wanted young unknowns. He’s not that unknown, but he’d never done anything as an actor before. So he auditioned. I auditioned literally thousands of young men with different combinations of young men. And he had it.

But then, what is ‘it’? Does Nolan mean that actorly X factor, the undefinable aura of screen presence that distinguishes the timeless movie idols from the common performing rabble? Or could ‘it’ be a massive built-in fanbase of millions that will unquestioningly pay up to see the established star regardless of how this film turns out? Could it be both?

Dunkirk marches into theaters on July 21.

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