Novel by the infamous Marquis de Sade, written during the years in which he was imprisoned in the Bastille, from 1774-1785. When the Bastille was stormed and burned, he thought the manuscript, consisting of little sheets of thin paper he had managed to hide and glue together into a scroll, lost. It later resurfaced, but was not published until 1935, owing to a rampant interest in Freud.

The story is of four noblemen (libertines, as they are called), newly rich on the corrupt reign of the last days of Louis XIV, who, wearied by their normal sex lives of depravity and aberration, embark upon a plan to lock themselves in a villa in Switzerland for 120 days, from November to February, along with 8 kidnapped girls under the age of 15 (chosen for their wealth, good breeding, and innocence), 8 kidnapped boys under the age of 15 (chosen for their noble background and innocence; both groups are virgins at every orifice), 8 large men ("fuckers", chosen wholly for the size of their dicks), the 4 wives of the noblemen (who are also each the daughters of one of the others), 4 old prostitutes (chosen by their hideoussness and deformity), and 4 middle-aged, experience whores who are each night to relate tales of their most interesting sexual exploits.

A strict set of rules is drawn up, indicating what everyone is allowed to wear and at what time of the day (if anything), who is to sleep with whom, the schedule for deflowering the virgins, who is allowed to go the privy (set up in the former villa's chapel) and who has to wait, and a system of punishments for anyone who deviates from the rules, either by disobedience or simply by failing to perform to the satisfaction of the 4 noblemen.

The first whore, Duclos, relates for the first month the 150 simple pleasures; nothing more exciting than water sports, blowjobs, coprophagy, and similar banal activities. The second whore, Champville, relates the complex passions, including child pornography and molestation, sex with mothers and daughters, and other group activities, usually combinations of the first set. The third whore, Martaine, are the criminal passions, including sex while under the effect of drugs and hallucinogens, self-mutilation, necrophilia, bestiality (with animals as diverse as bulls, monkeys, and swans), and sadism (such as a man who can only come on the wounds which he has just inflicted on a woman by cutting off her limbs). The fourth whore, Desgranges, tells of the murderous passions. Self-explanatory. Use your imagination.

It should be noted that the last three are unfinished.

This is one of the most philosophical of de Sade's works. The point of the stories is not only to work the 4 men into a frenzy, but have them discuss and analyse the limits of sexual aberration. de Sade makes clear his hatred of religion and the monarchy (hence the jail time). The general conclusion of the book is that morality is a crutch which hinders the human race; the only law is pleasure. His intent is to shock, and he claims to wish to "outrage the laws of both Nature and religion".

There is only one thing he got wrong; he claims that "never before has such a work been written, either in ancient or modern times".