"Underworld: Rise of the Lycans" is a dark and stormy prequel, reaching back to the Middle Ages to explain the roots of the centuries-long war between werewolves and vampires seen in 2003's "Underworld" and 2006's "Underworld: Evolution." The great mystery here, though, is Rhona Mitra's upper lip, which appears merely plump in some shots and grossly overinflated in others.