Nat Wolff, Finn Wittrock also star in the upcoming drama from director Henry Alex Rubin

Love and loyalty are pushed to the limit in EW’s exclusive trailer for Oscar-nominated Murderball documentarian Henry Alex Rubin’s upcoming thriller Semper Fi.

“‘Semper Fi’ is the motto of the U.S. Marines, and means ‘always faithful,'” reads Rubin’s director’s statement on his second narrative feature. “That motto also applies in deep friendships, where you are incapable of betraying each other, and stand up for each other no matter the pressure. If you’ve got just one person like that in your life, you’re lucky.”

Judging by the trailer (above), such ties that bind are tested when Callahan (Jai Courtney), a police officer and member of the Marine Corps Reserves, must battle personal demons and familial conflicts while attempting to help his younger brother, Oyster (Nat Wolff), navigate prison after he becomes embroiled in a violent crime.

“[We] wanted to write a film about that deep feeling of loyalty and love among friends. Before shooting, the cast spent lot of time training together, going out every night, cooking meals, partying, drinking, nearly getting into barfights, staying up till sunrise,” Rubin continues of the film’s production, which also included Gossip Girl‘s Leighton Meester and American Horror Story alum Finn Wittrock. “It was the most fun we’ve ever had on a set and that sense of true camaraderie is reflected on screen.”

Rubin admits that “From the outside, the film may seem like an action thriller,” though at its core it’s his love letter to bonds platonic and blood-based, “a meditation on the emotions and struggles of a group of friends who grew up together.”

Semper Fi hits theaters, digital, and on demand via Lionsgate on Oct. 4. Watch EW’s exclusive trailer above and see the poster below.

Semper Fi
Credit: Lionsgate

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