The season began with a 2 hour premiere on September 21, 2009. The fourth season contains volume five, Redemption. Madeline Zima will join the cast as Gretchen, Claire's quirky roommate. Rick Worthy will have a recurring role, playing Matt's new partner, an experienced and capable Los Angeles cop. Robert Knepper joins the cast as Samuel, a new villain. Ray Park has reportedly also been cast "for a sizeable arc".
