Can Dunkirk's Harry Styles match up to the acting of Heath Ledger in The Dark Knight? Christopher Nolan thinks so

Did you know that Dunkirk director Christopher Nolan was not aware of Harry Styles' stardom before the movie? Well, director Nolan cast the former One Direction singer completely based on his talent.

Also read: Dunkirk: New trailer for Christopher Nolan's WWII action thriller will take your breath away [VIDEO]

While casting Harry in a pivotal role raised a lot of eyebrows, The Dark Knight director said that he knew that he chose the right man for the role. The 23-year-old British singer who recently made his debut as a solo artist is portraying the role of a British soldier in the upcoming action thriller.

Director Nolan is better known to cast actors against stereotypes as he purely believes in his instinct. "As a director, I have to trust my instincts, my ability to figure out who's the right guy for the part. I'm not too worried about baggage," Nolan said in a recent interaction with Entertainment Tonight.

"I was new to Harry. I mean, I've heard his name from my kids, but I wasn't really familiar with him... What I was seeing [when he auditioned] was a very charismatic guy who clearly had a truthfulness and a subtlety in his ability to perform as a film actor."

Previously, when the 46-year-old director decided to cast Heath Ledger as Joker in the Dark Knight movie, it caused a stir amongst the critics.

"When I cast Heath Ledger as the Joker [The Dark Knight], it raised a lot of eyebrows and caused a lot of comment. I have to trust my instincts, and Harry was perfect for this part."

He has also shared his experience of working with the 23-year-old singer: "Harry was very committed and determined to just being one of the guys and coming there and learning what he could from the most experienced people around him and diving into the role feet first."

"I think he's done an incredible job on the film and I'm really excited to show it to people," Nolan added.

The acclaimed director further added, "What I'm hoping for, when people see the film, is I'm hopeful that they won't miss what he's done, because it's very subtle, very truthful and real."

Christopher Nolan was nominated for two Best Original Screenplay Oscars for Memento and Inception in 2002 and 2011 respectively.

Dunkirk, which is set to release on July 21, deals with the infamous Operation Dynamo during World War II. Thousands of soldiers of Britain, Belgium, Canada, and France were evacuated from the French harbour of Dunkirk as the Nazi forces invaded the country.

The cast of the movie features Mark Rylance, Tom Hardy, Cillian Murphy, Kenneth Branagh and James D'Arcy.

Watch the Dunkirk trailer below.