Someone who wears a blue mask, is squat and has giant hands are killing people and stealing jewelry and money. The witnesses are afraid to talk, despite the detective understands that the clues point to his friend Blue Demon. This is actually an evil plan hatched by the Count and a fighter called ' The Cossack ', taking revenge on Blue. In both the real Blue Demon campaign starts with his secretary and a detective to unravel the mystery.
In Montauban in 1944, Julien Dandieu in a surgeon in the local hospital. Frightened by the German army entering Montauban, he asks his friend Francois to drive his wife and his daughter in the back country village where Julien has an old castle.
100 miles north, a bit east and up, is Flåklypa... home of bicycle repairman Reodor Felgen and his two assistants - Solan Gundersen, morning bird and natural born optimist, and Ludvig who is a true pessimist.
During World War I, a German U-boat sinks a British ship and takes the survivors on board. After it takes a wrong turn, the submarine takes them to the unknown land of Caprona, where they find dinosaurs and neanderthals.