News of 'Homeland's third season has been much more slow in coming than that of 'Dexter's final season, given Showtime's decision to separate the two in launching their new series, but fragments of the Emmy-winning terrorism thriller have finally started to surface. 'Boss' star Amy Morton and 'Prison Break's Tracy Letts have joined the 'Homeland' season 3 cast in important recurring roles, but as whom?

'Homeland's third season has produced a number of shifts among the cast, between actors moving out of series regular positions and others moving up, but it appears the series has finally started casting its newest characters in preparation for a summer shoot. Via TVLine, we've learned that both 'Boss' star Amy Morton and former 'Prison Break' star Tracy Letts have signed on for recurring roles in the new season beginning September 29.

Morton will take the role of Carrie Matheson’s CIA appointed attorney Erin Kimball, while Letts will play Senator Andrew Lockhart, a powerful and commanding Committee Chairman. According to Showtime's press release, 'Homeland's third season picks up “during the aftermath of the horrific terror attack that decimated the U.S. intelligence apparatus, and prompted a global manhunt for the world’s most wanted terrorist — Nick Brody. As Carrie and Saul begin to pick up the pieces of their shattered professional and personal lives, they are swept up in the political and media firestorm surrounding the terror attack and the subsequent search for Brody’s whereabouts.”

Thus far, we know that in season 3 of ‘Homeland’ David Marciano (Virgil) and Diego Klattenhoff (Mike) are stepping down as series regulars to take reduced roles, while Morena Baccarin will reprise her series regular role as Jessica Brody, in spite of her wrongly-accused husband's absence. David Harewood, Jamie Sheridan and Navid Negahban have all exited the series, given their characters’ fates.

Well, what say you? Are you excited for a third season of 'Homeland,' premiering September 29? Who do you think will join the new season?

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