In England of 1921, Jack McColl's life has been wrecked. He is in prison after an altercation with a cop. He has no interest in the intelligence business anymore. His lover, Caitlin Hanley, has left him a couple years before to work on behalf of the Communists in Moscow. He has no future. Then his old Secret Service boss offers him a way out if he would travel to Russia to stop an MI5 agent from helping assassinate someone there, a job which will put him up against Hanley's new husband.