We’ve got some new casting developments regarding FX original programming to attend to today.  First up, Billy Bob Thornton has been tapped to lead the network’s upcoming limited series adaptation of the feature film Fargo. Writers/directors Joel and Ethan Cohen are involved as executive producers, and FX has announced that Thornton will play Lorne Malvo, “the rootless, manipulative man who meets a small-town insurance salesman and sets him on a path of destruction.”  The 10-episode series will feature a new “true crime” story and new characters, but Thornton’s role is similar to the one Steve Buscemi played in the 1996 Coen brothers film.

Novelist/writer Noah Hawley wrote all 10 episodes of the series, and production is set to begin in Canada this fall in anticipation of a spring premiere on FX.  Hit the jump for a couple of additions to the horror anthology series American Horror Story: Coven. 

Additionally, two more AHS regulars are returning for the third season of American Horror Story.  Subtitled Coven, the new season features a host of new characters led by Kathy Bates, but THR reports that season one actress Alexandra Breckenridge has joined the cast, and creator Ryan Murphy announced on Twitter that Denis O’Hare—who also appeared in the show’s first season—will play a role in the witch-centric third season.

Details regarding Breckinridge and O’Hare’s roles are unknown, but they join a pretty impressive cast that includes Jessica Lange, Emma Roberts, Angela Bassett, Patti LuPone, Gabourey Sidibe, Evan Peters, Sarah Paulson, Taissa Farmiga, Frances Conroy, and Lily Rabe.  American Horror Story: Coven will premiere on FX this October.