CANCEL your social life. Turn the lights out. Seal the doors. Elder Scrolls V: Skyrim is seriously addictive. Be prepared to invest heavily but rest assured: the returns are worth it. If you’ve been thinking about a divorce, now’s a good time: you won’t give your fraught spouse a second thought. You’ll be too busy saving up for a new horse (mine just got eaten by a dragon. Back to square one).

The first day I played Skyrim I was still going at half past five the following morning. The second day it was half past seven. At this rate I’ll run out of hours sometime next month.

Skyrim is an unbelievably vast, hand-crafted continent laid out for you to explore. Watch mammoths roam the plains; stalk stags through forests with your bow and arrow; hike to the top of frozen mountains or catch leaping salmon from a river. The emphasis is on choosing your own path.

The gameplay is pretty close to developer Bethedsa’s last big hit, the 2008 game of the year Fallout 3. This is certainly no bad thing and fans will spot parallels everywhere, right down to the drum-roll played when you level up. Many of Fallout’s notorious glitches have been ironed out (there is less floating furniture, and “sticky” bits of landscape, for example) but the main improvement is the combat system. Gone are the quasi-turn based sequences, which looked impressive but soon became repetitive, replaced by satisfyingly hefty hack-and-slash skirmishes that require tactics as well as a big axe.

The main difference, though, is the world in which it’s set. Instead of bleak post-apocalyptic wastelands, Skyrim is a living, thriving environment. The flip-side is it lacks the obvious hook of Fallout 3: the tongue-in-cheek 1950s American dream parody, piecemeal steam-punk shanty towns and irradiated inhabitants.

On paper, Skyrim could be mistaken for fairly standard Tolkein-esque fodder. Its developers must have brainstormed every fantasy-cliché they could think of. Its population of elves, trolls, orcs, dwarves and wizards reads like the credits from Lord of the Rings. But this soon falls away as you’re sucked into the complex, multi-layered plot and subtle Machiavellian political landscape. The paths you choose, friends or enemies you make, style of play, even the weapons you carry, can influence events across the game.

But all of this is superfluous to the world itself. You could just play through the main quest if you wanted (kill some dragons, absorb their souls, take sides in an epic battle for the future of the realm, yada, yada, yada), but this would miss the point.

The environment and its characters are everything – even the RPG system is stripped down, giving you a degree of choice without distracting you with too many spreadsheets and statistics.

The level of customisation you can give your character borders on the ridiculous.

You could spend an entire evening just designing a virtual face you will see for approximately ten seconds during your adventure, given that the point of view is either first person or over the shoulder. There are ten playable races to choose from (I opted for a dark elf) and you can even chose the amount (and shade) of dirt his or her face.

Skyrim’s drawbacks are few: some persistent niggly glitches, frustrating weapons-select menu and occasional over-long load times accounting for the majority of them. Skyrim’s makers say it can, in theory, last forever, with the game designed to spawn new missions ad infinitum. Based on the first 30 hours of gameplay, that still sounds too short.