The play features Holmes addressing the audience at an unspecified event, regaling them with the details of a case that he was involved in while his friend and chronicler of his adventures, Dr. Watson, was out of town. It takes Holmes awhile to get to the specifics, using the first half hour to give a lengthy exposition of his early years, and particularly his fondness for playing the violin and acting in plays.
The latter account is the first major misstep in the production, as Cahn's Sherlock brags about playing a marvelous Richard III, while the actor's own rendition of the lines from Shakespeare's play is rather poor. Since Holmes goes on to declare how he's been told he "would have made an actor and a rare one" and that "what the law had gained, the stage had lost," his words have the effect of an empty boast.
The case that Holmes eventually shares with the audience focuses on a beautiful American actress named Madeline, who claims she needs the detective's help in preventing jealous ex-lover Jeremiah from ruining her chances at a happy marriage. As might be suspected, both the case and the girl are more than what they seem.
The high point of the play is a segment in which Holmes gets to show off his uncanny deductive skills while in Jeremiah's home. Sadly, this is somewhat marred by a gaping plot hole; namely, that Jeremiah would show Holmes the object that leads him to make his deductions, especially considering how rude the detective had been to his host up until that point.
Director Eric Parness must share some of the blame for both the slack pacing and for not coaxing a more engaging performance from Cahn. Another curious production choice is that set designer Sarah B. Brown has the majority of her set covered in fabric for no discernible reason. I suspect that's a mystery that apparently not even Sherlock Holmes could solve.