Beckinsale's husband, Len Wiseman, directed those first two pictures as well, though he will not be returning for Underworld 4, as he appears busy making the, ugh, Total Recall remake. Wiseman will still act as producer, though. No other director has yet been attached.
The script is being written by John Hlavin with revisions by J. Michael Straczynski. Production will commence in Vancouver in March 2011.