Plot synopsis: The famous blue ruby is stolen in such an elaborate way, that only one villain can be suspected - Professor Moriarty. It is up to Sherlock Holmes to return it and, in the process, to turn a young pick-pocket on the right path. In the second part, Moriarty sets his sights even higher, stealing a top-secret submarine from the Navy. What does he need it for? Holmes is once again on the trail.