It is 1969 and MI6 double agent Paul Dark is giving a eulogy for Sir Colin Templeton at St Paul's Cathedral. Templeton had been chief of MI6 and has been killed by Dark. When Dark falters as his memories converge on him, acting Chief John Farraday comes to the lectern to intervene. A shot rings out and Farraday is killed, but was the bullet meant for Dark?

Dark gives chase and learns that the gunman is Italian and possibly belongs to a terror organization called Arte come Terrore. After a meeting with the new section chief, MI5 and the Home Secretary, Dark is sent to Italy to find out why there has been two killings. Once there, accompanied by a bodyguard, he meets again the local section head Charles Severn, who was at public school with Dark, and Severn's sultry wife Sarah who is the radio officer. They have arranged a meeting with the head of Italian military intelligence who will brief him about Arte come Terrore. Dark soon feels abandoned by his Russian masters and out of his depth in Italy, not knowing whom to trust if he indeed can trust anyone!