Several notorious criminals have vanished into thin air. A whisper has been received that the escape chain starts in London, but, when agent Paxton follows it, he winds up dead in the Thames with a 300-year-old bullet in him.

When representatives of the two organizations head to a country church to investigate the sudden reappearance of a man long thought dead, Steed and Emma are called in to help. It isn't long, of course, before murder rears its ugly head.

When Lucas, an agent investigating something subversive, gets off his train at the wrong station he is murdered. Has the crime got anything to do with a mole at the admiralty, a train ticket and a fiendish plot to kill the Prime Minister?