Franke, F. Sherlock Holmes und das Ungeheuer von Ulmen

Doctor Peeters from Trier, a former client of the master detective, forwards Sherlock Holmes a letter from a fellow student: According to an old legend, whenever a terrible fish monster emerges from the waters of the Maar in the tranquil Eifel village of Ulmen, a person must lose his life. The village schoolteacher Herbert Becher writes to his friend and swears that he has seen the beast in the flesh. Holmes is naturally drawn to such mysteries, and so he and his friend David Tristram make the arduous journey to the barren low mountain range to get to the bottom of the matter. When they arrive in Ulmen, they discover that the teacher Becher has died shortly before under mysterious circumstances. Holmes, who does not believe the local gendarme's version of the accident, then turns to a friend of the deceased, the dubious pharmacist Steinmetz, whose wife also claims to have seen the sea monster. When Holmes finds the address of an antique dealer in Trier in the deceased's house, he pays a visit to the venerable city on the Moselle. After another man dies a violent death in the village, the detective is left in no doubt that it was a cold-blooded murder.