Brad Pitt Sets Out to Save the Solar System in Third 'Ad Astra' Trailer

Courtesy of Venice International Film Festival

Tommy Lee Jones, Ruth Negga, Liv Tyler, Donald Sutherland, Jamie Kennedy, John Finn and Kimberly Elise also star in the film.

On Wednesday, 20th Century Fox released the third trailer for Ad Astra.

The science-fiction film follows astronaut Roy McBride (Brad Pitt) as he travels to the edge of the solar system to find his missing father (Tommy Lee Jones). As Roy searches for his father, he learns of a mystery that threatens the survival of humans on Earth. The astronaut's journey uncovers secrets that challenge the nature of human existence.

Ruth Negga, Liv Tyler, Donald Sutherland, Jamie Kennedy, John Finn and Kimberly Elise also star in the film. James Gray directed, produced and co-wrote the project alongside Ethan Gross.

The new trailer opens with Roy speaking to the press. "I do what I do because of my dad," he says as photos show his father during his own days as an astronaut. "He gave his life to the pursuit of knowledge 'cause up there is where our story's gonna be told."

Roy is next seen taking a top-secret psychological evaluation test where he is asked to describe his emotional state. He describes himself as "steady" and "calm" before dropping from a ladder and quickly descending into space.

As Roy continues to prepare for his journey, he explains that his dad was the first man to explore the outer solar system. "He was a pioneer, but there was much more to him than that," he says as clips show him both at work and in his personal life.

Roy's mission is later made clear when he explains that he is setting out to "stop uncontrolled antimatter reaction, which threatens our entire solar system." Drama ensues when he learns that some people believe his father is responsible for the solar system imbalance.

"What did he find out there in the abyss?" Roy asks as he watches old videos of his father. Intense clips follow of Roy's mission to find his father and protect everyone on earth.

"The world awaits our discovery, my son," the father says in a video at the conclusion of the trailer.

Ad Astra will be in theaters Sept. 20. Watch the full trailer below.