Lumen Pierce appears on the TV show Dexter.
Dexter is an American television crime drama mystery series that aired on Showtime from October 1 , 2006 , to September 22 , 2013 . Lumen Ann Pierce is a fictional character portrayed by Julia Stiles in the Showtime television series Dexter , season 5 . She goes out on her own and shoots one of her attackers , but panics not knowing what to do with his body ; she calls Dexter , who reluctantly helps her cover up the murder . Dexter realizes that she harbors a `` Dark Passenger '' much like his and agrees to help , in part to find his own closure following Rita 's murder . `` The Big One '' is the fifth season finale of the American television drama series Dexter , and the 60th overall episode of the show .