Ron Howard on 'Courageous' 'Rush' Star: Role Is Like 'Tackling Ali' (Video)

The director gives kudos to Daniel Bruhl and Chris Hemsworth as the trio pose during THR's cover shoot.

Chris Hemsworth and Daniel Bruhl are racing into theaters as Formula One legends James Hunt and Niki Lauda later this month. Ahead of their film's bow, The pair and director Ron Howard reveal secrets of their drama in the Sept. 13 issue of The Hollywood Reporter magazine.

"It was an intimidating thing to step into," Hemsworth tells THR. "Ron was looking at doing the film and I was looking for something similar, to star in a smaller film -- a smaller, character-driven drama that had an exciting backdrop like this."

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The film centers on the bitter rivalry between 1970s racers Hunt and Lauda, and also stars Olivia Wilde as Hemsworth's love interest.

Howard calls Bruhl "courageous" for taking on the roll of Lauda, whom he says was "as iconic as anyone" when and where the Spanish-born German actor grew up: "It is not unlike tackling Ali."

"That is always a frightening prospect," Howard says. "He tackled it with preparation, creativity and courage."

Howard adds that Hemsworth had a different challenge in portraying Hunt, who was a beloved yet mysterious figure.

"There was a tremendous amount of affection, but by the same token, he was a giant paradox. [Hemsworth] had to bring this complex character to life. In a lot of ways, it's why the scenes with Olivia Wilde were so important. It's the chance to see James Hunt remove the mask and be that vulnerable person," Howard says.

PHOTOS: 'Rush': Exclusive Photos of Ron Howard, Chris Hemsworth and Daniel Bruhl

Hemsworth praised the screenplay by Peter Morgan.

"That becomes your main foundation, and it was a really organic process from beginning to end, with Ron and Daniel and the whole cast," the actor says.

For more on Rush, read THR's cover story here, or pick up a copy of the magazine.

Rush hits theaters in New York and L.A. on Sept. 20 before opening nationwide Sept. 27 via Universal Pictures.