Released in September 2003, the film became a hit with horror fans and has since become a cult classic in its own right. Its blend of horror and action with monsters would set the stage for other genre combos to follow like Hellboy, I Frankenstein, Resident Evil, and others. Part of the magic of Underworld, along with its new take on the old myths of both vampires and werewolves, is that the creatures in the film are not the spawn of supernatural forces. There are no fears of crosses, mirrors, stakes, or any other of the Dracula-related weakness in the Underworld vampires. Hell, in one scene Selene looks directly into a mirror and guess what, she can see herself. The only vampire myth carried over here is their fear of sunlight as here it will kill a vampire as in most any other film of its kind.
The werewolves here get the most redo in that in the underworld universe gives us two types of beasts, the werewolf and the Lycan. The werewolf, such as the fore mentioned William, the first of his kind, can never again retake human form. But for Lucian, the subspecies the Lycan, he and others who he turns have to power to turn at will day or night….full moon or not. Where William and the victims he spawned are forever locked within a human/wolf hybrid form with the mindset of a mad beast, Lucian those he turned retain their human mind ever, and Lycan form.
Kate Beckinsale as the vampire assassin Selene is wonderful in the role and carries the movie with not only the power of a great warrior but also the grace and beauty of a woman with a single mission in mind…destroy Lycans at all cost. It is her story arc we follow as she thinks of nothing but killing the enemy, but once meeting Michael, she finds herself almost drawn to him setting itself up for a hint of a romance that would continue in the next movie. Also along the way, she discovers that her surrogate father turned her into a vampire. Viktor has lied to her about who murdered her family. She was told by him that it was the Lycans who killed her loved ones, but in fact it was he all along who murdered them and used the young woman’s own grief as a weapon, turning her into an immortal to fight his war with his enemy.