I.S.S. is a taut, straightforward thriller that delivers on its premise and doesn’t overstay its welcome. That’s not a backhanded compliment, especially these days.

Six astronauts are working aboard the International Space Station when they witness nuclear detonations on the Earth below. Three Americans, three Russians. Pockets of fire erupting across the United States. Communication ceases with ground control, and they’re left with little direction … until their respective commanders are ordered to take control of the I.S.S. at all costs.

That’s a big problem because working on the claustrophobic space station has given the astronauts a camaraderie that seemingly transcends national interests. Gordon (Chris Messina), the leader of the U.S. side, is a focused and rules-based astronaut engaged in a secret romance with Weronika (Maria Mashkova), a Russian cosmonaut. Christian (John Gallagher, Jr.) has kids back home and provides a somewhat paternal presence for the crew, too, giving gifts from back home whenever he returns on their Soyuz rocket. Nicholai (Costa Ronin) and Alexey (Pilou Asbæk) are the other two cosmonauts, bringing baggage and knowledge from their difficult Soviet upbringings. The last crew member is Kira (Ariana DeBose), a doctor dedicated to studying cures for genetic diseases in zero gravity. All six of them are challenged by the idea of betraying their found family.

But I.S.S. is a thriller, and thus, the backstabbing and misunderstandings start immediately. Nick Shafir’s script does a great job providing setups and payoffs throughout, steering away from twists or turns that undermine the character focus at the heart of the film. Director Gabriela Cowperthwaite navigates the tight, compartmentalized station with an eye on keeping characters closer than they’d like to be. The script and filmmaking work in tandem to establish the I.S.S. as a character of its own, with noises and rhythms that determine what moves its occupants can make as they struggle to gain the upper hand. Although a science-fiction thriller, the tension is grounded firmly in the character’s choices.

I.S.S. regularly returns to the characters viewing the burning Earth outside their windows. Even if they manage to take control of the station, well … what’s the point? Who is left on the ground? What use is a science outpost if their nations have been to smithereens? The utter pointlessness of their little conflict plays out as an apt anti-war metaphor that borrows from the great Cold War-era anti-nuclear parables.

There are a lot of bigger, more explosive directions a film with this premise could take. Fans of the excellent Apple TV+ series For All Mankind — myself amongst them — are particularly primed to watch a film about Cold War tensions erupting in space and expect something searing and exciting. Premise-wise, the comparisons are apt here, but I.S.S. really succeeds on its own terms thanks to a tight focus on characters, a solid script and efficient, thoughtful filmmaking.