Cassie (Britt Robertson) turns to Adam (Thomas Dekker) when she uncovers a secret about herself that she needs kept from the rest of the Circle, including Diana (Shelley Hennig). Meanwhile, Diana is thrilled when her grandmother Kate (guest star Stefanie Kramer, “Hunter”) drops in for a visit, but Charles (Gale Harold) is suspicious of his mother’s motives after Kate takes an unusual interest in Cassie. Meanwhile, Faye (Phoebe Tonkin) recruits a mysterious stranger named Lee (guest star Grey Damon, “Friday Night Lights”) to help her with a spell that could change the balance of the Circle forever. [...]

Source: The Secret Circle: Darkness