This is an automatically translated description

The novel is set in the Arab world at the end of the twelfth century. At that time, a sect of secret assassins was trying to seize both the material treasures and the souls of their followers, terrifying both the crusaders and their Muslim brothers with terror.

The son of a Baghdad garbage collector, teenager Ali, having heard the stories of merchants about overseas wonders, leaves his native city to sail to distant worlds. Along the way, he unwittingly witnesses a bloody assassin massacre and, worst of all, he comes across an invaluable treasure - a blue diamond. The assassins, realising that the boy has the diamond, start hunting for him. Ali escapes, each time one step ahead of his pursuers. During these escapes, he finds himself in different parts of Africa, in distant Madagascar, in amazing India, and even on the Indonesian islands. He becomes a skilful sailor and an experienced warrior.