"The World is Full of Married Men" is set in the vibrant backdrop of 1960s London and follows the life of David Cooper, a middle-aged advertising executive who engages in an affair with the young and ambitious Claudia Parker while still married to his wife, Linda. The novel delves into the complexities of their relationships, highlighting the hypocrisy of societal norms regarding marriage and fidelity. As David's life spirals out of control, he faces the consequences of his actions, leading to a dramatic exploration of love, betrayal, and redemption.