I'm jogging through an arctic wasteland: a barren, jagged landscape punctuated by precipitous cliff drops, perilous ice columns and the scant remains of civilisation – a crumbling rope-ladder here, a shipwreck there.
Snow crunches beneath my feet, swirls around my head and settles like powdered sugar on my backpack.
Then all of a sudden, out of the endless quiet, there comes a deep and ominous boom-boom-boom. I swivel my head to look behind me and overhead, where the white sky is obscured by the dark underbelly of a monstrous alien, trudging across the glacier, oblivious to my tiny form. I jog on. This, by the way, is not reality: it's virtual reality.
In truth, I'm sitting in a comfy chair at last week's E3 videogames convention in Los Angeles, wearing not a woolly hat but a headset: the final, retail version of the Oculus Rift virtual reality (VR) headset, to be precise, which is being demoed to the public for the very first time. The long-delayed device will not go on sale until the first quarter of 2016, but it has already revolutionised gaming.
Oculus founder Palmer Luckey put together the original Rift prototype in his parents' garage, 25 miles away in Long Beach, when he was 18 years old. That was 2011. The following year, John Carmack, creator of classic games such as Wolfenstein, Doom and Quake, heard about the Rift and asked Luckey whether he could demonstrate the device at that year's E3. The prototype, still held together with duct tape, proved groundbreaking.
For the first time, a device with mass market potential had genuinely delivered on the promise of virtual reality, after the clunky disappointments of the 1990s. Luckey launched a Kickstarter campaign to fund further development with a target of $250,000 (£157,000); 30 days later, it had raised $2.4m (£1.5m).
Even that figure seems modest now: last year, Facebook acquired Oculus for $2bn, with the product still deep in development. As he announced the deal, Facebook CEO Mark Zuckerberg described VR's potential beyond mere gaming. "Imagine enjoying a courtside seat at a game, studying in a classroom of students and teachers all over the world, or consulting with a doctor face-to-face – just by putting on goggles in your home," he wrote.
But this is a videogames convention, so I'm going to try a videogame. Three years after Carmack debuted the embryonic device, and 30 minutes after I joined the back of the line at the snazzy Oculus booth, I'm ushered into a small room that looks like the man cave from an Ikea show-home, handed a wireless headset and invited to slip it on as if it's a baseball cap.
The Rift looks and feels like a lightweight pair of blacked-out ski goggles. As soon as you put it on, you are immersed by the crisp sound of the built-in headphones and a 3D visual display that stretches beyond the field of vision.
Though I play with an Xbox controller, the next Oculus innovation is Oculus Touch, a pair of wireless handheld controllers that allow users to use their own hands inside the virtual experience. Reviewers have already tried them, and raved.
With the choice of several different genres of game from several major developers, I opt to spend my seven-minute demo with Edge of Nowhere, from Insomniac Games, a third person adventure in the Tomb Raider tradition. It begins, as described above, with my character avatar, "Vincent", running and jumping through the bleak polar terrain.
After the vast alien passes over my head, I escape into an echoing ice tunnel. Walking forward into the enveloping dark, I come across the bodies of a few dead men, lying half-obscured by the thick snow. Clinging to a frayed rope, I rappel down into a deep cavern, battling vertigo as I look down into the pit.
As I reach the bottom, a pack of monsters appears from nowhere and begins charging towards me. I sprint away through the cave complex, looking around for a way out as the floor crumbles underfoot.
I feel a genuine sense of danger unlike anything I've ever experienced in a game. I look behind me to see the monsters closing fast. I leap across a crack in the ice as it becomes a ravine, throwing out my hands in the hope that they'll reach the rock face on the far side...
The Rift, which is expected to cost about $400 to consumers, was originally scheduled to launch last year. Now it will be beaten to the market by some of the VR rivals it inspired: the cheaper Samsung Gear VR headset, designed to work in tandem with a Samsung smartphone, and the Vive, co-created by HTC and gaming software company Valve.
Whether the Vive outstrips the Rift, as some reviewers have predicted, is barely relevant: whatever the headset, the new VR experience is remarkable.
I have never owned a games console in my life, but the Rift makes me wonder whether this is what I've been saving up for all along.Reuse content