Underworld is a world.
The underworld or netherworld is an otherworld thought to be deep underground or beneath the surface of the world in most religions and mythologies . Underworld is a 2003 action horror film directed by Len Wiseman and written by Danny McBride , based on a story by McBride , Kevin Grevioux , and Wiseman . Underworld (film series) . It tells the story of Selene ( Kate Beckinsale ) , a vampire who works as a Death Dealer , killing the lycans ( Werewolves ) who allegedly slaughtered her family .