It describes the dangerous adventures of Joseph von Teofels in Sevastopol in the autumn of 1916.

In 1914, two German warships, the battleship Goeben and the light cruiser Breslau, had broken through to Istanbul, forcing the neutral Ottoman Empire into the world war on Germany's side.

With the Bosphorous controlled by the Central Powers, Russia's main southern ports were cut off from her allies, and as a result, the Russian army could receive arms and ammunition from the Entente only through the northern seas, along a very long and dangerous sea route.

Deciding to break the "German-Turkish lock" on the Black Sea, the Imperial Russian Navy began to build new battleships at the shipyard in Nikolaev.

To prevent this, Josef von Teofels is sent by the German intelligence service to attempt to destroy the battleship Empress Maria.