“In space, no one can hear you scream… your girlfriend’s name,” would be a good slogan for Slingshota psychological science fiction thriller about an astronaut who suffers severe romantic withdrawal symptoms during a trip to Saturn’s largest moon, Titan.

Starring Casey Affleck and directed by Mikael Håfström, the film at times seems like an intimate, understated variation of Christopher Nolan’s Interstellarand a variation of James Gray’s Ad Astra. But it is ultimately none of those films, relying instead on a lot of narrative red herrings and twists rather than heavenly miracles or emotional climaxes. The result feels more like a B-grade thriller, enhanced by a good cast and a script with some clever moves – which should help Slingshot end up on streamers without any problems after a theatrical release.

Affleck plays John, who is part of a three-man mission on the Odyssey 1 (shoutout to Kubrick), a long-range shuttle to Titan to find out if the moon’s abundant methane gas supplies could help combat the climate crisis. If that doesn’t seem logical or even feasible to you, just know that Slingshot is less concerned with the reality of interstellar travel or what to do with all that methane than with John’s deteriorating mental state as he ventures deeper into the solar system.

The astronaut seems to be suffering from a severe case of the space blues, haunted by memories of his girlfriend Zoe (Emily Beecham), whom he met at NASA (though she’s not called NASA here). She appears in his dreams every time he goes into hibernation, which is basically every other scene. Affleck was never a lively actor, and the fact that his character is in a state of semi-narcolepsy for most of the film fits his style well.

Things quickly spiral out of control when John’s fellow passengers, the bossy captain Franks (Laurence Fishburne) and nervous co-pilot Nash (Tomer Capone), start arguing among themselves after the ship is damaged in flight. Nash worries whether the titular “slingshot” maneuver — see the Nolan film for an explanation of how it works — will kill them all rather than catapult them from Jupiter to Saturn. But Franks is determined to complete the mission, despite the risks involved.

It’s pretty flat stuff, and Håfström frankly seems more interested in exploring John’s memories, nightmares, visions and his fluctuating psyche. As in his Stephen King adaptation 1408about a man who goes mad in a hotel room, the director has a knack for putting unreliable narrators in confined spaces that ultimately spell their doom. Leaving all the space stuff aside, Slingshot is essentially a thriller with only one character and only one setting, which constantly tests the viewer’s credibility with regard to what is happening.

Is John heartbroken over leaving Zoe on Earth for a multi-year trip to the other side of Saturn, or is he too emotionally closed off to care? Is Nash trying to sabotage the mission because he’s also completely unstable, or is he fighting for her life? And why does Franks suddenly pull out a gun to restore order to the ship? Even better question: Who brings a gun on a space shuttle?

At the beginning of the film, a generic female voice – that of the machine – warns John that the drugs that induce hibernation can have side effects. From then on, it seems to be just a matter of whether we actually experience those side effects or the reality itself. Slingshot goes into the third act, which presents us with a big and not revealing twist, and we wonder if anything what we see is really happening.

It’s enough to keep the viewer guessing until the very last shot and even beyond. But it’s also thin ice to stand on. If nothing is real, why should we care whether everyone dies in Odyssey 1 or not? And if Slingshot isn’t ultimately the story of a broken love story, then what is it really about? At its best, the film succeeds in capturing the lostness and despair that John experiences on his long, strange journey, and Affleck does a good job of conveying that tone as he repeatedly wakes and falls asleep.

Fishburne and Capone (a solid actor who should be in more films) are also strong, even if their characters aren’t given enough room to exist outside of John’s inner conflicts. In fact, there’s something thoroughly claustrophobic about it. Slingshotincluding a shuttle (designed by Barry Chusid, San Andreas), whose interior is a scaled-down version of the interior of 2001: A Space Odyssey. What is ultimately missing is the sense of vastness and fascination that such a journey usually brings. Despite all the millions of miles John supposedly travels, he never gets out of his own head, and neither do we.