1674, Mediterranean Sea, Maghreb. Don Cossack intelligence officer Ivan Platov, sent to the Ottoman Empire under the guise of the Turkish sailor Hassan, is completely legalized and enters service, becoming the youngest officer of the Turkish fleet. Hassan is brave, smart, well educated and can find an unconventional way out of a dangerous situation. But he has another valuable quality - he is incredibly lucky. And this cannot escape the attention of the powers that be, who are trying to use such a valuable person for their own purposes. Suddenly, Hassan finds himself in the very center of dangerous events unfolding on the Maghreb coast. The interests of European states are closely intertwined with the interests of the Maghreb rulers - vassals of the Turkish Sultan, who want to leave the subordination of the Ottoman Empire. Long-standing discontent, skillfully fueled by emissaries from France and Austria, leads to a riot in Tunisia and open confrontation with the Turkish Sultan. Of course, this is impossible to forgive. And the Turkish reconnaissance group, which includes Hassan, is sent on the captured Al Yasat shebek to rebellious Tunisia.