Bernard Kramer is an ex-Royal Marine who is wealthy enough to escape the daily grind of work - but not the boredom that has set in since his Service days have been left behind.
His antidote to this is to periodically undertake to solve problems for selected recommended clients who usually pay only his expenses. This often leads him into dangerous situations which combat his growing disenchantment with civilian life.
Sandra Yarrow appeals for help to restore her brother's good name. Peter Creel was a co-director of an arts reproduction company until he was convicted of child kidnapping and imprisoned. Shortly after his release he was killed, the victim of a hit-and-run driver.
Kramer interviews the 'victim' and her mother, and concludes that they are both hiding something. By a ruse, he obtains an admission of false testimony from the girl. He then visits the dead man's company, and obtains information about co-workers and circumstances leading to his arrest from the remaining director, Charles Jarvis.
One of Peter Creel's former colleagues, Bob Desmond, lives within a few miles, and Kramer seeks further information from him. On arrival at the house he discovers that Desmond and his wife have been murdered.
From Jarvis' information Kramer realises that the company's Egyptian suppliers figure largely in the cause of Creel's death, and flies to Luxor after escaping two attempts on his life. In Egypt the attempts continue and Kramer breaks into the factory at night, only to be knocked unconscious after discovering that the place is a centre for cocaine smuggling.
He awakes in a stone cell, presumably awaiting interrogation, but eventually frees himself and escapes. After returning to Luxor on foot he is able to arrange a loan from a friend in England, before the gang try again to kill him.
Kramer recognises a girl who he saw at the factory while waiting for darkness to fall, and makes his way back there to abduct her. He forces her to disclose the wherabouts of the gang's London distribution centre and the name of the UK controller - Christine da Quintana.
Back in London he meets a former comrade who has become addicted to cocaine, learning that the gang is known as 'The Sagittarius Ring' and is widely feared. At the distribution centre Kramer narrowly misses being killed but discovers that Christine da Quintana is attending a conference of executive drug traffickers in Vietnam.
In Hanoi he is a marked man. The Sagittarius Ring have followed his every move and Christine da Quintana tells him face to face that he has little time to live. His only ally is a local police chief who advises Kramer to leave the country, although Kramer senses that the man's true intention is to promise limited help.
Through underground connections, Kramer obtains a military device with the destructive capability he needs. He conceals himself in the rural hotel where the conference is to take place, until he is satisfied that his actions are justified.
He is discovered and the gang close in as he races to prepare his only defence .
