Fanboys rejoice, Kate Beckinsale is back in those skin tight leathers.  She has signed on for a fourth installment in the Underworld franchise.  The as-yet-unnamed film is based on a script by John Hlavin, which is being re-written by Joseph Michael Straczynski (Babylon 5, Superman).

According to Deadline Hollywood, production Underworld 4 will start in Vancouver in March.