The pitch for The Callisto Protocol is an enticing one: Creators behind the Dead Space series of sci-fi survival horror games would finally make a spiritual successor to that franchise, nearly 10 years into its dormancy at Electronic Arts. The Callisto Protocol would also build on the elements of Dead Space — creeping through cold, abandoned space environments inspired by Alien’s Nostromo, being doused in gore ripped from Event Horizon — with a decade of experience and maturity to hopefully make something better.

Developer Striking Distance Studios instead made something largely divergent — a Dead Space spiritual successor with some, but not all, of the best parts of Dead Space. In some ways, it’s a step back.

The Callisto Protocol opens with space trucker Jacob Lee, played by actor Josh Duhamel, pulling off One Last Job. That mission, naturally, goes sideways when an apparent terrorist group sabotages his cargo ship, crash-landing him on Jupiter’s second-largest moon, Callisto. Jacob and his ship’s saboteur, Dani Nakamura (played by The Boys’ Karen Fukuhara), find themselves thrown into the moon’s Black Iron Prison. Disaster doubles when Jacob wakes to find himself outfitted with an invasive implant called a CORE, in the midst of a catastrophic outbreak, and surrounded by mutated monsters wreaking havoc. Jacob, armed with only a stun baton, fights to escape from his wrongful, inexplicable imprisonment.

Where Dead Space focused on high-tension gunplay and the tactical severing of limbs from zombielike grotesques, The Callisto Protocol puts meaty, action-heavy melee attacks at the center of its combat. The game’s monsters swing at Jacob with haymakers, which he can dodge by leaning left or right. It’s a mechanic not unlike Nintendo’s Punch-Out!!, where Jacob can bob and weave until he can find an opening to bludgeon his attacker into a bloody mess. Later, Jacob gets access to pistols, shotguns, and rifles, which become complementary to melee combat, not wholesale replacements. He also gets Jedi-like powers, thanks to the battery-powered GRP, a glove that can grab and throw objects — including the monsters themselves.

Early on, combat can feel frustrating. Jacob’s lumbering movement gives everything a sluggish, inconsistent feel, and knowing when to dodge, or even when you’ve been struck by an attack, can be unclear. Understanding the game’s timing — finding The Callisto Protocol’s groove — takes time. Eventually, switching between melee, gunplay, and GRP controls starts to click.

Even in a one-on-one fight, a successful encounter might involve a series of dodges, bashes, surgical pistol shots (yes, you can remove enemies’ limbs here, too), and telekinetically throwing an enemy to give yourself some space. The GRP occasionally allows for a one-hit kill, letting you throw enemies into spikes or whirling fans, turning them into a chunky spray of gore. But the GRP is a highly limited resource and needs to be used sparingly. Later encounters switch things up, pitting Jacob against sentry robots that can instantly kill him from afar, and blind monsters where stealthy kills with a shiv aren’t just preferred, they’re all but necessary to succeed.

Still, the game has a general sense of sluggishness, a seemingly intentional choice to give Jacob and enemies a sense of weight and impact. Some inputs, though, like quick weapon switching, don’t seem to register sometimes, which is a huge problem in difficult encounters. Turning on “performance mode” in The Callisto Protocol’s graphics settings does help alleviate that sluggish feeling. By default, the game uses a more cinematic, graphically impressive visual mode. But the improved frame rate — and more responsive inputs — afforded by performance mode make a huge difference.

But even once you do settle more into The Callisto Protocol’s rhythm, combat scenarios often feel unrefined. Smaller enemies pop up with little to no warning, for instance, locking Jacob into button-mashing quick-time events that drain his health. Monsters also pop up directly behind you, making some encounters feel downright unfair. Dead Space had its “monster closet” moments that delivered fun, well-earned jump scares — but mutant zombies emerging from grates in the floor out of your line of sight? Far less enjoyable, particularly when paired with the game’s disorienting camera movement. That’s nothing compared to multiple moments where the game throws mobs of enemies at you. These are the worst parts of The Callisto Protocol, where any earned tension snaps and turns immediately into pure aggravation. Multiple difficulty spikes pushed the game past the realm of “enjoyable challenge” and into that of “unfair masochism.” I eventually switched to easy mode out of necessity.

The game’s checkpointing system is also inconsistent. There are frequent checkpoints, thankfully, but they often occur seconds into a boss battle, with no time to heal, reload, or reach a position of safety to recompose.

You do unlock upgrades over time that make Jacob slightly more powerful. At 3D-printing stations, you can spend money acquired from chests, corpses, and by selling contraband to improve weapons and the GRP. But no upgrades make Jacob a monster-slaying god, and credits are doled out sparingly enough that it seems impossible to upgrade and unlock everything in a single playthrough. (Or, currently, in a second playthrough, as The Callisto Protocol does not yet have a new game plus mode where upgrades will carry over. That’s due early next year, according to the developer.) Choices about which weapon or device to upgrade can feel tough: Is an extra few seconds of battery life for the GRP worth more than a harder-hitting stun baton? Should I blow credits on the increased ammo-count node to open up the damage boost for bullets later?

The Callisto Protocol’s 3D-printing stations, run by the United Jupiter Corporation that runs Black Iron Prison, may offer my favorite bit of world-building/commentary in an otherwise pretty straightforward sci-fi horror yarn. Posters strewn throughout the prison inform the security workers there they can spend their so-called Callisto Credits to upgrade their gear, forcing them to spend their own money on the very supplies necessary to protect themselves against the inmates.

Beyond that, the story of The Callisto Protocol and the disaster of Black Iron is told mainly through Jacob’s interactions with fellow prisoners Elias and Dani, as well as the warden and his sadistic captain Ferris. Players can also acquire audio recordings from inmates and guards, but unlike similar audio logs in the Dead Space games, which played through the games’ diegetic holographic UI, The Callisto Protocol requires the player to stop what they’re doing and dedicate their full attention to listening to each recording. Given that some of the recordings I listened to added nominally to the story, they started to feel inessential to the game’s narrative. I walked away satisfied with, but not surprised by, The Callisto Protocol’s story.

Where The Callisto Protocol excels is in its atmosphere and environments. The game’s cold, metallic, industrial world is gorgeously realized, giving Black Iron Prison a hard, tangible, weighty feel. Jacob slogs his way through air ducts, through pools of sewage, and between dangerous machinery that can shred him (and enemies) in an instant. Beyond the walls of the prison, players will explore an equally dark and terrifying moon surface, where they’re battered by snow and wind. The Callisto Protocol features an impressively, painstakingly created world; it’s an expensive-looking game, and not just for its Hollywood talent. (In addition to Duhamel and Fukuhara, Striking Distance and publisher Krafton also enlisted actors Gwendoline Christie and Michael Ironside for a six-episode podcast prequel to The Callisto Protocol.)

The Callisto Protocol is extremely linear, with only a few diversions, very little backtracking, and almost no puzzle solving. The original Dead Space’s holographic wayfinding system is absent here, but there are plenty of arrows and graffiti acting as literal signposts to your next objective. In other words, the game does not want you to get lost, even though I can’t imagine doing so anyway. After completing The Callisto Protocol in about eight hours — not counting the dozens of failed attempts in the section that broke me into selecting easy mode — I don’t see a reason to return to the game until Striking Distance adds the new game plus mode, or additional story content. What’s more, the manual save system doesn’t make it easy to return to previous chapters, meaning I’d have to do a full run-through to collect anything I missed.

With The Callisto Protocol, Striking Distance proves it can capably create nerve-wracking moments of tension and horror with a well-crafted combination of sights, sounds, and atmosphere. The studio was smart not to create a one-to-one copy of Dead Space — especially with original publisher Electronic Arts now returning to the franchise with a remake due next month. But still: The Callisto Protocol could have borrowed a few more lessons from its spiritual inspiration, and further refined its mechanics to make a game that plays as good as it looks.

The Callisto Protocol was released on Dec. 2 on PlayStation 4, PlayStation 5, Windows PC, Xbox One, and Xbox Series X. The game was reviewed on PS5 using a pre-release download code provided by Krafton. Vox Media has affiliate partnerships. These do not influence editorial content, though Vox Media may earn commissions for products purchased via affiliate links. You can find additional information about Polygon’s ethics policy here.