Philipp Gabert and his best friend, Dr. Nicolas Amberg, are hiking in the mountains. Suddenly, Philipp suffers a strange attack of weakness and loses consciousness. Nicolas is only just able to prevent his fall. But the friendship between the two men is burdened by a problem: Nicolas is secretly in love with Philipp's wife Julia - and feels like a traitor. When the men set off on another mountain tour, only one of them returns. Was it an accident or murder?

An ethnologist and his daughter set off from Heidelberg on an expedition to the jungles of Zanzibar. Strange incidents occur as soon as they arrive in Africa, which suddenly seem to be connected to the snake on the young woman's shoulder: Indian secret society members want to make her their queen.