This prequel completes an Underworld Trilogy which up to this point has been criticised for relying on style rather than substance. But this film which charts the start of the Lycan/Vampire war gives us some character development - along with the dark, violent, yet slick visuals delivered previously.
Our view of the Lycans so far has been one of savagery in comparison to the refined qualities of the Vampires, this is rebalanced in Rise of The Lycans. We see the Lycans as the slaves of the Vampire, forced to guard them during the day, and collared so that they cannot change form without fatal consequences. The Vampires still appear civilised, but it's clearly seen that their coven is built on a foundation of slavery, corruption, and exploitation.
Lucian - the first of the 'new' Lycans plans to escape and lead his own kind to freedom, only his plan is complicated by his love affair with Vampire daughter of ruling Elder, Viktor.
What ensues is an action / romance with Werewolves, Vampires, and lots medieval slashings and gore. Again a lot of effort has gone into marrying this film into the back-story already introduced during the other two films, and also into Vampire folklore itself. This means that the three films complement each other brilliantly. I've said before that the first two films certainly aren't bad - but they are best viewed together to give a true sense of the epic scope, and now with this film that sense is intensified.
The cast has been put together well and Bill Nighy seems to relish his role as Viktor. He hams it up but instead of feeling overacted, the flamboyancy adds to the Gothic theatrics of the film. Michael Sheen's welcome return as Lucian brings with it the vulnerability and bubbling undercurrent of revolution needed for the character's role. His scenes with lover Sonja are convincing and as an audience, you rally behind him and believe in his cause.
In a nutshell: This fills in some gaps, most of which we didn't know existed until this film. This stands alone as a pretty good film, again (and at the risking of repeating myself) when you view this as part of the trilogy it considerably increases the viewer experience. Sheen and Nighy impress, Sheen is a hero without being too heroic, and Nighy is superbly creepy. The blood spurting action is there, but there's a meaningful story too. We now have three films that create a story across an epic scale from the middle ages to present day.