Heroes is looking to cast several roles for season 3. The latest one is for a villain. 
A villain. Eric Doyle is  a 30s-48yo big, hideous and horrible Caucasian male. He is a disgusting, villainous man who delights in controlling others. The guest star will be needed for Episode 6 of season 3. There’s no word on who will play the part but I’m more interested in the type of character. Villain, huh.. How many villains are we looking at now?
A storyteller. Tim Kring was also said to be looking for an Australian aboriginal actor in his fifties who …read more

Heroes has a new hero villain in the making – super-speedster Daphne. Brea Grant got the part to play this new villain, and from what she says, Daphne may be a thief, with a super-speed ability.
Brea talked about Daphne stealing a family heirloom it seems from the Nakamura family and Hiro caught her just in time. “He stops time right as I grab it, but in that second it took him to grab it, I almost make it out of the office.” Masi had talked about her in passing, referring to his new archenemy as his Joker.
source: spoilerfix