In 1689, young Peter I and Princess Sophia fought for the Russian throne. Sensing the weakness of the empress, adviser Avtonom Zerkalov kidnapped her illegitimate daughter, intending to hand her over to Peter. But the girl was freed by teenagers far from politics - boyar Dmitry Nikitin, popovich Alyosha Leontyev and peasant son Ilya (an allusion to the “three heroes”).

The villainous fate scattered her friends around the world. One became a Cossack, another became a mercenary and spy, and the third became a brilliant mechanic. Now, ten years later, the participants in the dark history of 1689 will meet again and find themselves involved in a conspiracy against Emperor Peter Alekseevich.