McNiven, 29, has a list of credits including Hildy on Mad Men and Anna Milton on Supernatural. She has also appeared on Desperate Housewives, New Amsterdam, and Law & Order: Criminal Intent.
In a press release, Syfy also confirmed the casting of actor Robert Knepper (Heroes, Prison Break) as Simeon (story). He will appear in six episodes.
Both characters make their debut in the season premiere, “Intervention,” GateWorld has learned.
The network also confirmed that Season Two will begin airing in the fall of this year.
NEXT: Read the full press release