US Casting: Zima and Knepper join the Heroes; Ford reports on Dexter

We're going to get a lot of casting news through summer, as US shows are in pre-production for their Fall return. Madeline Zima (Californication) is joining the cast of Heroes' fourth season as "edgy outsider" Gretchen, Claire's college roommate. Also, Prison Break's Robert Knepper (who played T-Bag) is joining the superhero drama as Samuel, "a Jim Jones type -- charismatic but evil, with a twisted sense of humour, who will veer into the lives of all heroes." Both are signed for six episodes.

It's also been revealed that Ray Park (Darth Maul in Star Wars Episode I: The Phantom Menace) is in talks to play a role, along with Deanne Bray (The L Word).

Meanwhile, Courtney Ford (Cold Case, Ugly Betty) has been cast in Dexter as a reporter.