The Sixth Doctor finds himself at Bletchley Park, during World War Two...where his life and that of Constance Clarke are about to collide...This is the first of a new run of stories with Colin Baker as the Doctor, a role he's been playing for Big Finish since 1999. New companion Constance Clarke is played by Miranda Raison, a familiar face from British stage and screen including Spooks, Poirot, Merlin, Doctor Who and 24: Live Another Day...CAST: Colin Baker (The Doctor), Miranda Raison (Constance Clarke).