Sounds like we finally get to meet Cassie’s father John Blackwell (Joe Lando) in the 15th episode of The Secret Circle.
The episode airs on February 9, and here is an official description from The CW.
CASSIE’S PAST COMES BACK TO HAUNT HER — Cassie (Britt Robertson) is stunned when a notoriously evil figure from her past shows up on her doorstep (guest star Joe Lando, “Dr. Quinn Medicine Woman”). However, her surprise quickly turns to suspicion when he asks her to return the medallion she found in the wreckage of the fire that killed their parents. Cassie storms off but is captured by Eben and his band of witch hunters. Jake (Chris Zylka) offers to trade himself for Cassie’s freedom and when Adam (Thomas Dekker) realizes they’re in trouble he calls the Circle. Meanwhile, Faye (Phoebe Tonkin) and Diana (Shelley Hennig) are concerned when Melissa starts spending more time with Callum (guest star Michael Graziadei). Gale Harold and Natasha Henstridge also star. Brad Turner directed the episode written by David Ehrman (#115).