Cthulhu: The Cosmic Abyss review: stunning UE5 visual design and ambitious ideas impress

Cthulhu: The Cosmic Abyss is a compelling pitch that veers from the frustrating to the blindingly ambitious: it’s a dive into Lovecraftian horror not often experienced; a detective story wrapped in strange and abstract puzzles; a sci-fi adventure that leans into the obscure and, at times, feels too fragile in how it holds itself together.

Set in 2053, a world where occult phenomena are no longer left in the shadows but tracked and documented, Cthulhu: The Cosmic Abyss casts you as Noah, an investigator for the Ancile, an organisation tasked with handling the unexplainable and the plain weird. Following up on a missing-person lead, and after being dragged out of a portal in a waterlogged basement, Noah soon looks into the disappearance of miners deep in the Pacific Ocean. There’s a little of the brilliant Underwater in the premise, and I’m all in for a developer trying something new with the mythos.

That's because, for the first time in a video game, Noah’s investigation is leading to the sunken city of R’lyeh itself. Not so much a city as a forgotten, crumbling prison, its logic-defying architecture twists corridors into impossible shapes, spaces fold in on themselves, and reality starts to feel unreliable. It’s a bold centrepiece, and on many occasions you’ll venture into a temple corridor only to emerge where you started, in one moment, hundreds of feet above where you entered. That said, The Cosmic Abyss never quite feels as surreal as the Cthulhu-inspired Still Wakes The Deep, which hints at the cosmic without saying it out loud.

The Cosmic Abyss explores new depths

That blend of near-future sci-fi and weird cosmic horror works beautifully, as sterile corridors flicker with failing screens while submerged temples feel like they’ve been waiting centuries just for you to arrive. It all comes together in a way that feels ambitious, as Big Bad Wolf is throwing everything at the screen to make its take on R’lyeh feel solid and alive.

But while the Unreal Engine 5-made world itself is detailed and beautifully lit, solid and tactile, much of that ambition rests on the game’s clue-revealing scanning mechanic, which is its standout idea and, at times, lifts the game from a standard detective adventure into something more engaging.

When I first started this review two weeks ago, the scanning mechanic crashed the framerates, even in Performance mode. But since then, I've been dipping in and out, and the good news is that Big Bad Wolf has been optimising this mechanic. It's patched the game three times during this review period and made improvements, making each return more playable than the last.

The scan mechanic now works smoothly, even on a base PS5 in Quality mode. The ability to sweep environments with sound frequencies to uncover clues is especially inspiring in a world that’s deliberately vague and untethered. When you’re lost, and you will be, that sonic ping becomes a lifeline. It’s not just functional either, it’s visual, sculptural almost, revealing the (literal) bones of the world in shifting lines and contours, rocks, statues, bodies, all pulled into focus and often used to tell the hidden story of R’lyeh and its forgotten alien architects and guardians.

When it clicks, it really clicks. Deep in the temple caverns of Chapter 3, piecing together fragments of documents, uncovering strange carvings, and less pleasant remains, feeding them into the 'Vault', the game's version of a mind palace, there’s a genuine sense of satisfaction. It can feel like you’re constructing meaning out of a patchwork of found lore and scans, and when conclusions are made and a solution found, that’s where The Cosmic Abyss feels at its best.

There’s also an interesting layer of player agency threaded throughout The Cosmic Abyss that taps into the Cthulhu mythos. Your actions influence Noah’s 'Corruption' level. Dig too deep into the world and its horrific, unfathomable secrets, scan on, examine something nasty, and it rises; focus on logic and deduction, and you can keep it at bay and even lower it. Injecting Noah with a cosmic 'fungus' offers free scan deductions, so it's best used sparingly.

The Corruption system adds a degree of tension to exploration in an otherwise threat-free adventure, even if, in practice, curiosity tends to win out – on my first playthrough, I scanned everything because I wanted to know and understand the world I was sinking into, and it didn't end well. That push and pull between clues, leads, and knowledge and a very bad thing happening, feeds nicely into the game’s multiple endings, giving replays a real sense of purpose.

A stuttering scanner

As you progress deeper into R’lyeh, the world design becomes denser, often more vertical, and the puzzles follow a similar arc. Early on, things feel clean and logical, with clues leading naturally to solutions, and progress makes sense. Later, though, the game leans harder into its more esoteric side, and the penultimate chapter’s sprawling astrological puzzle is a standout that demands you grab a pen and paper like you’re back in the ‘90s (partly I'm old-fashioned that way and partly because the Vault becomes a little jittery when overloaded on clues). This is a satisfying tent-pole puzzle to plot through, with several routes to reaching the same conclusions, though it’s a shift that might catch some players off guard.

When and if you do get stuck, Noah has an AI, called Key, that can offer tips and help make more sense of the scans and clues, often as simply as summarising the lore you've found into helpful questions to push you towards an answer. Key can be limited if you want to adjust the difficulty, but it's a novel in-world mechanic for balancing the challenge that offers hints without breaking immersion.

Though it has to be said that the loop of scanning and piecing together clues and deductions remains the same from start to finish, aside from piecing together what R’lyeh is and why it exists, uncovering the world's narrative, the puzzles themselves remain a simple act of scanning, reading, and connecting the dots. That loop and the density of clues increase, but rarely veer from the core idea. A curveball twist or two would have been welcome to stave off repetition. But the option to follow one of two detective paths (embracing or avoiding Corruption) is just enough to retrace back into The Cosmic Abyss' watery worlds, as it did for me.

You can't turn away

Still, I did keep going back. Partly for the puzzles, partly to chase different endings, but mostly because of the world itself. There’s a richness to the design, a willingness to get weird with the Cthulhu mythos, that’s hard to ignore. Unreal Engine 5 is working hard to present lighting that dances across surfaces, water that refracts and distorts, and grotesque, fanged sculptures of unknowable beings that feel tactile and present.

This is a lovely-looking game, and after the updates, even when scanning heavy geometry, my PS5 handled Quality mode nicely, and I often found myself dawdling, simply taking in the world around me and admiring the design. Big Bad Wolf knows how to pace its world, too, with claustrophobic corridors opening to vast vistas of towering statues and cosmic starshine.

The fact that I do find time to stop and look up also highlights another slight issue with the game's sense of danger, or lack of, something I touched on earlier. There's only one moment in the descent into The Cosmic Abyss where a genuine threat occurs, when Noah's fear manifests as a chest-busting leach, as for the entire game, you're reslly only fighting an existential threat, the spectre of Cthulhu lurking in the shadows, at the edges, and your own desire to poke around a little too far and spark more Corruption. It's a design choice by Big Bad Wolf, but it also means there's never an urgency to Noah's quest.

Cthulhu: The Cosmic Abyss can be a little messy at times, no doubt about it. Some bugs I encountered (interactions failing, clues that can't be scanned, and more, all forcing a chapter restart) have been fixed in updates, yet new ones have appeared as well (an invisible wall blocking my route to the final chapter). The developer is clearly earnestly swatting them; just go in eyes open that the ambition here comes with a cost.

But it is ambitious, even if the lack of real danger can undercut the immersion the game works so hard to build. Yet there’s something sticky at the game's core, a combination of smart storytelling, excellent puzzle design, creative visual design, and a genuine love for cosmic horror that keeps it together even when the tech behind it can stumble. What's impressive is that, despite this unevenness, Big Bad Wolf has crafted a Lovecraft world I kept returning to, a game I couldn't stop thinking about, if you will, and one that rewards more often than it frustrates.