Kit Harington and Jennifer Elhe have reportedly signed on to star in a big screen adaptation of Spooks: The Greater Good.

Game of Thrones' Harington will play the lead role of ex-MI5 agent Will Crombie as he investigates the mysterious escape of a terrorist prisoner.

The original TV series' director Bharat Nalluri will helm the project with Jonathan Brackley and Sam Vincent penning the script.

Stephen Garret, producer of the original series, told The Hollywood Reporter, "With Spooks: The Greater Good we've set out to make a gripping, cinematic, contemporary spy thriller – one that builds on the history of the show and its legacy of questioning the world around us, but which also delivers as a stand-alone film or a new, global audience."

The film is due to begin shooting in early 2014.