Tricia Janine Helfer (born April 11, 1974) is a Canadian actress, voice actress and former model. She is best known for playing the Cylon model Number Six in Ronald D. Moore's re-imagined Battlestar Galactica series (2004–2009) and voicing Sarah Kerrigan in the StarCraft video games (2010–2015). She played Charlotte Richards / Mom on the FOX series Lucifer (2016–2018).