Simon Templar is hired by a friend in the book publishing trade to protect one of his stars, a secretive recluse named Amos Klein who writes a popular (and lucrative) series of adventure novels about a manly and suave spy.
In this fictionalised account of the Great Train Robbery, career criminal Paul Clifton plans an audacious crime: the robbery of a mail train carrying millions in cash.
Sam Laker is an American industrialist, working in Britain, who has just been awarded an international award for industrial design. He is planning to travel to East Germany to attend a trade show and show off his invention, taking his 10 year old son with him for a holiday. Meanwhile a British Intelligence officer who served with Laker in the Second World War decides to use the opportunity of Laker's trip and his lack of an intelligence profile to coerce him into carrying out an assassination.