The great Sherlock Holmes said: “Discard the impossible, and no matter how incredible what remains, it is the truth!” Amateur detective Erasmus Darwin is of the same opinion! The goal of his life is not just to investigate mysterious mystical crimes, but also to find a RATIONAL explanation for mysticism!

At the bottom of a Scottish backwater lives a terrible prehistoric monster, sacredly guarding sunken treasures? An ancient demon's curse befalls ANYONE who touches a huge ruby? On a night when the wind is blowing from the east and the full moon is shining in the sky, a werewolf killer appears at the Lambeth mill? In the underground tunnels live the ancient “people of the hills”, hiding from human sight for thousands of years?

Doctor Erasmus Darwin and his friend and assistant Colonel Pole begin an investigation!