It is the time of the third crusade. A public hanging has just taken place in the middle-eastern town of Acre and three soldiers stand on the podium displaying the bodies of the victims to an angered crowd, who are baying for their blood. Way up on the battlements a solitary figure in white is watching the developing scene.
Then we're following the white watcher as he's walking through the crowd. You can see that this is in-game footage, as the figure pushes people out of the way and tries to move through the heaving throng without disrupting his cover too much. When he's finally spotted, it's too late for the guards on the podium; one receives a bolt in the belly, a second is toppled off the gallows by a blow from a crossbow and only the captain is left. He struggles to get his sword out of his scabbard, but before he can Altair, the assassin, is on him, pushing his retractable blade into the man, before turning and fleeing through the crowd, pursued by growing numbers of guards...
Assassin's Creed follows Altair the assassin - his name translates as 'Flying Eagle' - as he seeks to bring peace to the Middle East of 1191 AD, by decapitating the heads of the warring factions. However, Altair's abilities don't merely extend to killing people. First off, he's an amazing athlete - Ubisoft Montreal haven't forgotten their Prince of Persia heritage, so he can Le Parkour his way up onto the rooftops and battlements of Jerusalem, Acre, Damascus and other Middle Eastern towns. The crowd is his best friend providing cover and escape routes, as well as hiding him from the eyes of his enemies. Finally, if he has to fight, Altair will avoid swordplay, as a solid blow will prove fatal; instead he'll dodge and twist around enemies to execute or flee them as quickly as possible, with a range of instant kills or escape moves.
The HUD is curiously futuristic, perhaps to tie in with the later parts of the trilogy, though there's no confirmation that they will be set in the same universe. If the rest of the series looks as impressive, we can guarantee that this is one creed we'll happily follow.