A crack army unit - the Special Marine Corps, consisting of five British and five American soldiers - is on a top-secret mission to investigate and, if necessary, eliminate, an illegal private army on a tropical island in the mid-Atlantic. Tony is one of the British soldiers, and this is his first proper action.
What the tough, hard soldiers find out when they investigate the island is that their enemies don't shoot them with bullets. They have discovered a powerful weapon, the Pheromone Bomb, which produces a gas - and anyone affected by the gas is filled with irresistible homoerotic urges. Tony and his best mate Mervyn are among those who escape the initial disastrous encounter with the island's private army, but what are they going to do with an enemy who with a blast of his secret weapon can turn lifelong confirmed heterosexuals into helpless, rampant homosexuals?