The life of an assassin, eh? One minute you’re everyone’s favourite, killing mercilessly with a song in your heart and the next you’ve botched a mission and are being forced to salvage your reputation by killing nine unpleasant people scattered across the Holy Land. Such is your role as Altair, a member of the assassin’s brotherhood unaffiliated with either the Templars or Saracens during the third crusade.

The plot of Assassin’s Creed is startlingly weird, filled with murder, traitors and twists you’ll undoubtedly see coming but will enjoy nonetheless due to the panache with which they’re executed. Credit goes in no small part to the four cities in which the action takes place – Jerusalem, Acre, Damascus and Masyaf – each of which is dripping in detail and atmosphere. Gleaming domes and towering spires litter the skyline, while bustling alleys reverberate with the laments of citizens watching their homeland being ripped apart by the Crusades. And these citizens aren’t just for show; they can help or hinder you depending on your actions towards them.

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It’s a stunningly evocative world that’s given added zing by the ‘free-running’ feature you use to cross it. Rather than leaping over objects manually, you simply hold down the spacebar and right mouse button and Altair does all the work, whether that’s leaping across rooftops or scaling castles. At first, it feels a little shallow, but you swiftly appreciate the simplicity and flow when being chased.

This grace carries into the combat. For each of the nine blokes you kill, Altair is rewarded with new skills that transform later encounters from a simple clash of swords into escalating ballets of carnage. It’s meaty and satisfying, and will have you picking fights with guards just to try again. In fact, the city and fights are so good, you’ll be three hours into Assassin’s Creed before you realise that, plot aside, you’ve already seen all it has to offer.

Satisfying battle and movements, and rich, detailed environments are the best bits of Assassin's Creed

While Altair has to take out nine targets, each mission breaks down in exactly the same way. You receive your target, travel to their city and scale a dizzyingly tall viewpoint to work out where everything is. In so doing, your map fills with information-gathering side quests, which need to be completed before you’re allowed to go off and stick something pointy in your quarry’s back.

The side quests are invariably dull. Take eavesdropping, for example, in which you press ‘F’ to listen to a nearby conversation and, well, that’s it. Or how about pick-pocketing: you get close to somebody, press Shift and, erm, you’re done. The PC version adds four new missions, the pick being a rooftop-race challenge, but while this adds variety to the mission selection they still lack challenge and become tiresome. This is compounded by the fact that should you fail – by nodding off halfway through, say – you simply make yourself scarce for a few minutes and the missions reset, removing any sense of potential tension.

Thankfully, you only need to complete two of these side quests before you’re allowed to go after your target, which is where the game really lets itself down. Those hoping for stealth and planning will be disappointed. There’s no watching your target for an opportune moment, or plotting an escape route to make a speedy exit. Instead, you wait for a cut-scene to play and then attack. It’s almost impossible to do this without alerting the guards, at which point you’re swiftly engulfed in a slightly longer and tougher version of the same fight you’ve already been through a hundred times before with the city guards, which is a huge shame.

Which sums Assassin’s Creed up neatly. It starts brightly and tires quickly. It isn’t a bad game, and the plot makes it worth playing to the end, but it never scales the same heights as Altair.