Boswell's Fairies is an often humorous tale of life during basic training of Her Britannic Majesty's Corps of Royal Marines. Paul Johnson is unhappy with his middle-class (striving for upper middle class), parents, his girlfriend, and his job. To change his life he joins the Royal Marines. He rejects his father's recommendation that he apply for a commission and knows he will have to dumb-down his background and education if he is to fit in with other recruits. Jack Mason left his foster home to join the circus and drifted into wrestling. Fed up of 'paying his dues' on the wrestling circuit, he opts for a life of stability in the elite branch of the armed services. The two men become firm friends, or oppos. Their sometimes arduous training and constant search of female companionship and fun teach Paul and Jack a lot about themselves and the serious business of living.
Sergeant Francis Bowell is an immaculate drill instructor in charge of H Squad, the squad of which Paul and Jack are members. The sergeant's job is to remain their mentor throughout the ten-month period of basic training at Deal, Poole, and Lympstone, where those who finish will be awarded the coveted Green Beret. His homophobic prejudices, partially obscured behind humour, are accepted without question. The sergeant christens his squad 'Boswell's Fairies' and instructs the young men to declare their new identity to the world. None of the thirty squad members foresees the consequences of the label and many take pride in it.
After six-weeks confined to barracks (concrete ships) in Deal, the recruits are allowed ashore. Paul and Jack do not find the local women easily accommodating and they end up at a dance hall where they do battle with a bunch of local teddy boys. They later line London's Mall for the arrival in state of Haile Selassie and thereby learn something about the people they have sworn to protect. After giving an immaculate drill display and passing out as The Queen's Squad, they go to Poole where they experience a glimpse of the Special Boat Service while they cavort with French girls who live in the area.
At Lympstone H Squad learns to tackle the assault course, the Tarzan course, the endurance course, the regain tank, plus the physical abuse of instructors. The pair meet two women who introduce them to marijuana and discover Paul is a talker and Jack a muncher. One squad member is a boxer and they travel to Plymouth to watch him contest for the area championship. Another dates a woman who later admits she is a prostitute and asks him to become her pimp. The youngest and most naive squad member falls for a girl and wants to marry her so they can have sex. One weekend Paul and Jack each have dates with three women but can only accommodate two of them.
When the squad learns of Boswell's arrest for killing a homosexual in a pub toilet, the pair's girlfriends counterpoint Paul's and Jack's blinkered defense of their admired leader. Towards the end of the training at the Commando School the squad, carrying full kit, endures a thirty-mile route march, and learns how to jump out of moving vehicles. Having earned the hallowed headwear and certain to be posted to another command, the two friends ponder their relationships with their girlfriends, Jill and Audrey.
