Brad Pitt is on a mission. In the new sci-fi thriller Ad Astra, the star plays Roy McBride, an astronaut who heads into space to look for his father, the renegade astronaut Clifford McBride (Tommy Lee Jones). Watch an exclusive new trailer for the poetic, mysterious drama above.

Director and co-writer James Gray first brought the project to Pitt three or four years ago, he told Vanity Fair in a recent interview, after the Pitt produced his film The Lost City of Z. He and the role were a perfect match: “There’s a very mythic quality that is attached to a movie star like that,” said Gray.

But though Roy may seem like an all-American hero type, Gray said the character has a lot more going on under the surface. “It’s really more of an attempt by us to examine a schizoid personality, and how that is preferred for astronauts in space travel, because you don’t have to connect emotionally,” he said. Ultimately, Pitt “plays someone with schizoid tendencies”—though Gray said that this is not an outright character trait, but more of the “deep background” baked into the part. Gray also praised the actor for doing “remarkable” work in the film.

The film explores the dark side of a father-son dynamic. Roy uncovers shocking things about his father over the course of the story, delving deeper into his past as he searches for the truth about Clifford’s whereabouts. In a way, Gray said, the story is about “the last grasp of the patriarchy.” Clifford is essentially a “Buzz Aldrin-type figure—if he’d gone mad in deep space.”

The writer-director was inspired to write Ad Astra after researching the first nuclear chain reaction in Stagg Field in the 1940s. At the time, some feared that the experiment would set off a dangerous, unstoppable reaction: “science out of control,” Gray mused.

In a previous interview, the filmmaker said Ad Astra was his attempt to make the most realistic depiction of space travel in a film— a sentiment he now would like to walk back, to some extent. “I cursed myself with those words,” Gray said, good-naturedly. “What I meant was to try and adhere to the possible at all times. We have done that, actually.”

The film’s cast is rounded out by Ruth Negga, Donald Sutherland, Liv Tyler, John Ortiz, and Kimberly Elise. Ad Astra will hit theaters on September 20. Check out the new poster below.

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