Julia Stiles has joined the cast of Showtime's "Dexter" for the show's upcoming fifth season.

The actress will appear in 10 episodes in the upcoming season, playing "a mysterious young woman who forms a unique relationship with Dexter (Michael C. Hall) in the wake of the death of his wife."

Production on the fifth season begins this month and also includes the return of Julie Benz, whose character, Rita, was killed off last season.