The movie's A-list roster also includes "Closer" co-stars Julia Roberts and Clive Owen.
Wilkinson also earned an Oscar nod for his work in "Michael Clayton."
In "Duplicity," Thornton and Wilkinson will play the CEOs of rival pharmaceutical companies while Roberts and Owen will portray corporate spies, the entertainment industry trade paper said.
Thornton has starred in "Sling Blade," "Armageddon," "Pushing Tin" and "Bad Santa."
Wilkinson is best-known for his roles in "Shakespeare in Love," "The Full Monty" and "In the Bedroom."