I don’t know exactly what’s stalking me, but I know it’s horrible. It looks a bit like an emu, but made of metal and wires. It clunks around the room noisily, a blue spotlight beaming from what I assume is its head, making scary, distorted shrieking sounds. When I get near it the screen tears and fragments like a worn-out VHS tape. I could ignore it and stay in this dark, safe corner forever, but there’s a terminal across the room I need to access. If it sees me, I’m dead. But I have no choice.

It’s clear early on that Soma is by the same people who made Amnesia. As I crouch in my corner, waiting for the robot to pass, I get flashbacks to crouching in another corner, hiding from another monster, in The Dark Descent. But this is a far cry from Brennenburg Castle. Soma is set in an underwater research base, with claustrophobic metal corridors that remind me of Alien’s similarly eerie Nostromo. And it’s clear from the very start that something has gone horribly wrong here.

As I explore the abandoned base I notice strange bio-mechanical tendrils bursting through walls and forming clumps on the floor, and a sticky black liquid of unknown origin drips from the ceiling. It’s like the place is being eaten by some encroaching horror, and the constantly flickering lights aren’t making the place any more inviting. You don’t know why you’re there, or what the base is for, and neither does the main character. At first I thought I was on a spaceship, then I walked through a glass tunnel and saw shoals of fish swimming above me. It’s a brilliantly atmospheric setting, reminiscent of the hard-edged, understated sci-fi films of the 1970s.

Things get weird when I meet a survivor. Or, rather, a machine that thinks it’s a survivor. A rusty old robot is trapped under a pile of rubble and is pleading for me to help it. I talk to it and discover that it’s utterly convinced it’s human. “I can see my arms!” it shouts, confused, when I insist it’s not. It’s a deeply odd moment, but my fascination is interrupted when I throw a power switch and accidentally kill him. Or it. I’m still not sure which. Did I murder someone? Am I a robot? I love how reluctant the game is to explain anything. It keeps you guessing: about the base, its purpose, your robot stalker’s motivation, if any, and your reason for being there.

You piece the story together through environmental details. There are documents, drawings, and notes scattered around the base, and the main character has some special power that lets him touch machines and hear echoes of past events. You can log into computers and read people's’ emails or listen to audio logs. Hey, it is a horror game after all. But the information you uncover is never explicit. If anything, it usually makes the situation more confusing. Why are other research bases around the world closing? Why was this one abandoned? Why is that emu trying to kill me?

The Dark Descent had a ‘sanity’ meter and limited lantern oil to worry about, but this ongoing character management has been reduced in Soma – although not eliminated entirely as in The Chinese Room’s Amnesia: A Machine For Pigs. I’ve not completely figured out how it works yet, but whenever the emu ‘kills’ me, the screen fades to black and I seem to wake up moments before it happened, giving me a chance to try again. But the more I get spotted, the more messed up the screen gets, with woozy distortion effects and colour separation. Sticking my finger in a glowing pod thing clears the effect and, I’m guessing, restores my ‘health’. It’s a peculiar system, but makes the game less frustrating than Amnesia could be.

Soma’s shaping up to be a pretty special horror game. It’s not a massive leap from Amnesia, but the production values are much higher and the new sci-fi setting is wonderfully realised. But it’s the story that’s really grabbed me, especially these robots who think they’re human. The idea of your mind being trapped in a machine is really quite chilling, and a great basis for a dark sci-fi horror story. I made it to that computer terminal in the end, quietly slipping past the emu, but I don’t think it’s the last I’ll be seeing of my disturbing metal friend.