One Drop of Blood, first published in 1932, opens with the murder of Dr. Carl Koenig, the chief psychiatrist at the Mayfield Sanitarium in the midwestern city of Hamilton. The weapon used to kill Dr. Koenig is the proverbial "blunt instrument," and the psychiatrist's office has been trashed, presumably by the killer. Is the murderer one of the quite possibly insane patients? Or is it a perfectly sane, if devilish, plot created by someone else- perhaps one of the other staff members at the Sanitarium? The primary detective is James "Bonnie" Dundee, special investigator for the District Attorney's office in Hamilton. It is Dundee who points out the discrepancies in the evidence which make it pretty certain that they are dealing with a sane and cunning killer. And it is also Dundee who will discover what will eventually prove to be the critical piece of evidence: a drop of blood at the murder scene where there really shouldn't have been a drop of blood.