When Dr. Watson ends up renting rooms in Baker Street with the eccentric Sherlock Holmes, he finds that he has let himself in for a great deal more than he imagined. He is called upon to help the budding detective solve a perplexing mystery, involving a dead body found in a locked room. Although the body shows no signs of having been attacked Holmes is convinced that a murder has been committed. As Watson looks on, he uses his exceptional powers of deduction to unravel a case that involves both kidnapping and thwarted love.