A fourth film, shot in 3-D, is set to be directed by Måns Mårlind and Björn Stein with a release date of January 20, 2012.

Kate Beckinsale has officially signed on to reprise her role as Selene and screenwriter John Hlavin has stated that the movie will not be a prequel.[3] Production on the film is set to start in March 2011 in Vancouver with Tom Rosenberg, Gary Lucchesi, and Len Wiseman producing.

On November 22, 2010, it was reported that the film is tentatively titled Underworld: Awakening and the following plot synopsis was given:
“After being held in a coma-like state for fifteen years, vampire Selene (Kate Beckinsale) learns that she has a fourteen-year-old vampire/Lycan hybrid daughter, Eve, and when she finds her, they must stop BioCom from creating super Lycans that will kill them all."
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http://en.wikipedia.org/wiki/Underworld_(film_series)