The star picked up the coveted Best Actor prize at February's (11) Academy Awards for his role as stuttering British monarch King George VI in hit film The King's Speech.
But rather than ride on the wave of his movie success, Firth has decided to challenge himself in a stage role, according to Britain's Mail on Sunday.
Firth is allegedly in talks to star alongside Scott Thomas in Harold Pinter’s Betrayal this autumn (11).
It would be the first time Firth has stepped onstage in over a decade.
A source tells the publication, "Colin has wanted to go on stage for a long while. He’ll do Betrayal after he completes filming Gambit with Cameron Diaz and Alan Rickman."