Idris Elba is in talks to join the cast of Pierre Morel's action thriller The Gunman. Sean Penn stars as Martin Terrier, a international operative who is betrayed by the organization he works for. Idris Elba will portray a mysterious agent named Dupont. The project is an adaptation of Jean-Patrick Manchette's book The Prone Gunman. Pierre Morel is directing from a script by Pete Travis. Silver Pictures' Joel Silver, Andrew Rona and Steve Richards are producing. Idris Elba earned a Golden Globe for his role in the hit BBC series Luther and can be seen next in Guillermo del Toro's sci-fi Pacific Rim. Production is scheduled to begin later this month in Barcelona.