The movie is actually a prequel to the previous duology of movies. It starts off as the base for the next two movies. The story is about the love between the princess and daughter of the Vampire King Victor and the first of the Lycans (werewolves who can control their abilities). Needless to say Victor does not approve between this unholy alliance and his fury ensues. Battered and loveless, Lucient (the first second generation werewolf) arises from slavedom and starts a rebellion to overthrow the vampires.
Overall, its a good movie with all the familiar faces of the duology back in action. It also tells us small information about some of the characters. Why are they what they are in the next two movies. Pity you dont get to see Kate Beckinsale much in this movie!!