The Havana Quartet is a series of detective novels written by Cuban author Leonardo Padura. The series follows the character Mario Conde, a former police officer turned writer, as he investigates various crimes in Havana, Cuba. The novels blend elements of mystery with rich cultural and historical insights into Cuban society. The quartet consists of four main books: Face of the Water, Havana Blue, Havana Gold, and Havana Black. Each novel explores different themes, such as love, loss, and the complexities of life in post-revolutionary Cuba, while also providing a vivid portrayal of the city and its people.