After a remarkable and impressive career in the army Jack Spencer was given a dishonourable discharge, taking the blame for his colonel's blunder. He discovers that there is no place for him in civilian life and, in despair, he begins to look for jobs he considers beneath him. Finally he takes a job as chauffeur and odd job man to a young Brigadier Ashford, who he later discovers is an arms dealer. He makes the most of the job and is soon training troops in South America, as well as selling weapons for a revolution. Jack is convinced it is all quite legal and is sent to Africa, only to find himself mixed up in a violent and bloody uprising involving Ashford himself. Narrowly escaping a firing squad he returns to South America to sort out what was left after the rapid but successful revolution. He is appointed Head of Security for the new President but soon discovers that both the old exiled president and a mining tycoon have designs to seize the running of the country. Jack's task is to prevent them.