Lee Pace (The Normal Heart) will also join the project, which is currently shooting on location in Europe and follows Armstrong's rise to fame, battle with cancer and scandal with steroids.
The cast also includes Ben Foster (Orpahns), who stars as Lance Armstrong, and Chris O'Dowd (upcoming Of Mice and Men), who plays journalist David Walsh, with Guillaume Canet and Jesse Plemons.
John Hodge wrote the screenplay based on sportswriter Walsh's book "Seven Deadly Sins: My Pursuit Of Lance Armstrong."
Tim Bevan, Eric Fellner, Kate Solomon and Tracey Seaward are producing.