The Harlequin is the fifteenth book in the Anita Blake: Vampire Hunter series of horror/mystery/erotica novels by Laurell K. Hamilton; it was released June 5, 2007.

The Harlequin exists to police and punish vampire leaders who violate various rules, such as Malcolm's resistance to the blood oath.

Anita keeps them alive by feeding on first Rafael and through him, all the wererats in the city, Belle Morte and later, all the swanmanes in the United States via the swan king, Donovan Reece.

They not only succeed, but determine that the Harlequin members were planning to take over Jean-Claude's territory and not operating on official Council orders.

The Mother, a spectral presence, grew stronger with each flicker of resentment, its form taking shape, a chilling promise of its imminent and terrifying arrival in the world.