10/07/2017 12:38 PM AEST | Updated 10/07/2017 12:38 PM AEST

Christopher Nolan Didn't Know How Famous Harry Styles Really Was

Sounds like the director wasn't a huge One Direction fan.

When you're a massive director like Christopher Nolan you probably don't pay attention to everything going on in the world. You're probably too busy polishing your shelves and shelves of awards or... you know... actually directing movies.

Well that point was proven when Nolan was asked about how he came to cast former One Direction member Harry Styles in his upcoming World War II epic 'Dunkirk'.

"I don't think I was that aware really of how famous Harry was," Nolan told 'The Hollywood Reporter'. "My daughter had talked about him. My kids talked about him, but I wasn't really that aware of it. So the truth is, I cast Harry because he fit the part wonderfully and truly earned a seat at the table."

Styles' co-star Mark Rylance had a similar run-in with the youngins in his life, admitting that he learned who the singer was from his 11-year-old niece.

"She was just more excited than anything I've ever done because I was going to be acting with Harry Styles."

Rylance said his niece was more excited he was working with Harry than when he, you know... won an actual Oscar.

'Dunkirk' is a historical thriller, based on the true events of the Dunkirk evacuation of World War II through the perspectives of those on the land, sea and in the air.

The film stars Styles and Rylance, who are joined by Fionn Whitehead, Tom Glynn-Carney, Jack Lowden, Kenneth Branagh, Cillian Murphy and Tom Hardy.

Whitehead, Glynn-Carney, Lowden and Styles sat down for a candid roundtable conversation where they discussed the immense scale of the film. Due to Nolan's massive production, the four young actors often felt completely immersed in the action.

While Nolan may not have been the biggest Styles fan going into the project, Styles had nothing but compliments about working with the director.

"He leads by example," Styles said, "he's like the first one there, the last one to leave."

You can watch the full roundtable in the clip above. 'Dunkirk' opens in cinemas across Australia July 20.

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