Robert Knepper has signed on to play Antonius in The Hunger Games: Mockingjay Part 1 and The Hunger Games: Mockingjay Part 2.

The character does not appear in the Suzanne Collins novels, but a report from Variety reveals that Antonius is the minister to President Snow (Donald Sutherland). It isn't known how big a part this mystery character will play in the two-part sequel.

The actor joins a cast that includes Jennifer Lawrence (Katniss Everdeen), Josh Hutcherson (Peeta Mellark), Liam Hemsworth (Gale Hawthorne), Philip Seymour Hoffman (Plutarch Heavensbee), Julianne Moore (Alma Coin), Natalie Dormer (Cressida), Stef Dawson (Annie Cresta), Evan Ross (Messalla), Lily Rabe (Commander Lyme) and Patina Miller (Commander Paylor).

Francis Lawrence is directing the final installments from two screenplays provided by Danny Strong. Both movies will be shot back-to-back in Atlanta.

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Robert Knepper currently stars in the TNT drama series Mob City. He is best known for roles in Prison Break and Heroes, along with big screen appearances in R.I.P.D., Transporter 3 and Hitman.