This game is what games need to be more about, it is extremely high quality and was very groundbreaking for its time, and even now there are few games that have great gameplay but actually focus on an amazing storyline.
As some have already mentioned, this game has a Zelda kind of feel, but it's following a much more mature route of concentrating on story and plot rather than Zelda.
I urge you to buy this game to support the game and most importantly to support the sequel which is in development but Ubisoft are very hesitant to release due to poor sales of this first game.