en Cuevana 3. As a geophysicist, Leonard Gehra is now known for his theories on silver mining. However, Leonard originally comes from the mining town of Buchenrode in the Harz Mountains, which he left after the mysterious death of his father in the 1970s. Now Leonard is to return to his homeland to put his previously theoretical method of mining silver in the old mining tunnels of Buchenrode into practice. The town is on the verge of bankruptcy after Ferdinand Türnitz decided to close his mines. Leonard, in whom the town's last hope is now placed, sets to work and discovers a long-kept secret during his investigations, which does not leave his father and Türnitz out in the cold.