Five close friends, all of them married, share a loft to meet their mistresses. One day they find the body of a young woman in the loft. Since there are only five keys to the loft, the five men begin to suspect each other of murder.

Vincke and Verstuyft are one of the best detective teams of the Antwerp police force. When they are confronted with the disappearance of a top official and the murder of two prostitutes, the trail leads to the almost retired assassin Angelo Ledda. Since Ledda starts showing symptoms of Alzheimer’s, it’s getting more and more difficult to complete his contracts. When he has to murder a 12-year old call-girl, he refuses and becomes a target himself. While Vincke and Verstuyft are chasing him and counting the corpses, Ledda is taking care of his employers.

The family of the Belgian prime minister is kidnapped. To get them released, he must murder the American president.

For five men, the opportunity to share a penthouse in the city — in which to carry on extramarital affairs — is a dream come true, until the dead body of an unknown woman turns up. Realizing that her killer must be one of their group, the men are gripped by paranoia as each one suspects another. Friendships are tested, loyalties are questioned, and marriages crumble while fear and suspicion run rampant.