Tatyana Bekesheva regretted that she had come to Siberia to excavate an ancient fortress - she could not understand her feelings for the leader of the expedition, Anatoly, who invited her here. But she ended up in the very place where three hundred years ago her distant ancestors met - the envoy of Peter I Miron Bekeshev and the Siberian princess Aidyna! During the excavations, they accidentally stumbled upon a rich burial. Looks like it's Aidyna herself! Then something terrible began to happen: those guarding the found treasures were attacked, and Tatyana witnessed a quarrel between the archaeologist Fedor and an unknown person, who suddenly pulled out a knife and stabbed him to death! Was it really Fyodor who brought the “black diggers” to the camp? Tatyana remembered: her ex-fiancé asked to take him on the expedition!