Hollywood A-listers Brad Pitt and Tommy Lee Jones are heading into deep space in Ad Astra, a science fiction epic set in the future. The stars are in line to join The Lost City of Z  director James Gray, who co-wrote the script with Fringe writer Ethan Gross.

It was announced in February that Pitt would star in the film. Pitt's character is Roy McBride, a "slightly autistic space engineer" who goes looking for his father who left on a one-way mission to Neptune 20 years ago to find signs of alien life. McBride must search for him and discover why the mission failed. It's expected that Jones is in talks to play the father who went missing.

Ad Astra will be Pitt and Gray's third collaboration. Pitt actually produced The Lost City of Z through his Plan B Productions, and was expected to star in the film but had to pull out due to scheduling conflicts. Charlie Hunnam stepped into the role meant for Pitt and although the film didn't set the box office on fire, the former Sons of Anarchy star did win more critical praise than for his summer tentpole film King Arthur: Legend of the Sword. As far as Pitt and Gray are concerned, the two were once attached to make The Gray Man at one point, but that never materialized.

In an interview with Collider in April, Gray compared Ad Astra with the Joseph Conrad novel Heart of Darkness, which was a story about a voyage up the Congo River in Africa. The story depicted the harshness of life in Africa as the protagonist advances deeper into the heart of the continent. Published in 1899, Heart of Darkness has been called one of the greatest texts in Western literature. Just as Heart of Darkness took its protagonist into dangerous, unknown territory, Ad Astra is expected to do something similar with Brad Pitt's character as he navigates the outer edge of the solar system.

"Ad Astra" is a Latin phrase that means "to the stars." Pitt's trip "to the stars" in Ad Astra would mark the actor's return to the science fiction genre 22 years after his role as Jeffrey Goines in the critically acclaimed time travel movie Twelve Monkeys. It was this role that earned Pitt his first Academy Award nomination.

Production for Ad Astra begins in September. No release date has been set.

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Sources: Deadline