The film begins in the north-east of the Belgian Congo in 1933. Following reports of mysterious deaths in the region over several years, the Belgian colonial authorities arrest and put on trial a group of men suspected of belonging to the Mambela sect and of being responsible for these deaths as Aniotos, men who kill like leopards. Among them is Mbako, ritual chief and presumed leader of the Aniotos or leopard men. As the film progresses, the role of the accused is reversed and the colonizers' disregard for traditional customary law, social structures and traditional leaders and chiefs, as well as their devastating impact on local traditions, are scrutinized.