Sherlock Holmes has retired. But when MacDonald asks him to take on another case, he says yes. There have been some mysterious murders, and there are no visible causes for the deaths. At the same time Holmes gets this case, Graf Udo Von Felseck gives him another case: find a young and missing prince to prevent war between Germany and England. But Von Felseck is not as honest as he seems.
Certain events which had an impact on Sir Arthur Conan Doyle, while he was still a medical student under the supervision of Dr. Bell, his teacher and mentor, on whom the character of Sherlock Holmes is partly drawn from.