I highly recommend it. They actually made a prequal (sp?) that's worth watching. The movie actually tells you how the war started without trampling on the other two and negating some stuff. It also brings you full circle to the first scene in the first Underworld. In my opinion it was very well done unlike a lot of others I've seen.

__________________
"BOY: On a hot summer night, would you offer your throat to the wolf with the red roses? GIRL: Will he offer me his mouth? BOY: Yes. GIRL: Will he offer me his teeth? BOY: Yes. GIRL: Will he offer me his jaws? BOY: Yes. GIRL: Will he offer me his hunger? BOY: Yes. GIRL: Again, will he offer me his hunger? BOY: Yes! GIRL: Yes. BOY: On a hot summer night, would you offer your throat to the wolf with the red roses? GIRL: Yes. BOY: I bet you say that to all the boys!" -Meatloaf