(Some Spoilers) With him being in such great demand by both the the local, as well as out of town, police department in solving so many of it's unsolvable crimes the obviously burnt out "Crime Doctor" Dr. Robert Ordway, Warner Baxter decides to finally take his first vacation in over five years. Dr. Ordway drives upstate to the little quite town of Brookfall to do some hunting fishing and most of all relaxing. Sadly for the good doctor it did't turn out that way.
As soon as Dr.Ordway got to Brookhill it was quarantined because of a typhoid epidemic with him being recruited by the state troopers and local medical clinic to help in the inoculation of the towns population. Doing the best he can Dr. Ordway examining the blood samples of those who succumb to the deadly disease finds that the towns barber as well as it's smooth talking and handsome womanizer Ward Beachey, Trevor Bardette,did't die from typhoid at all! It turns out that Benchey was poisoned and made to look by his killer like he died of that disease.
Being that Dr. Ordway's friend Dr. Sam Millerson, Griff Barnett, who's house he staying at last treated Benchey with his home-made brew or potion of bark roots berries and bitters he's the prime suspect in his murder. It's also reviled that Dr.Sam was very angry with Benchey for not going to him for medical treatment over the last year. Benchey was going to the newly opened county medical clinic that's taking business away from him. All this suspicion of Dr. Sam being Benchey's killer becomes moot later on when Dr. Sam himself is murdered! It now becomes very clear, especially to Dr. Ordway, that Bencheys murder had nothing to do with business matters between him and his killer! There's something far more deeper in Benchely's death and closer to home. Benchy's sexual exploits with the ladies in town may well have caused one of those ladies outraged and vindictive husbands or boyfriends to murder him.
It's the murder of Dr. Sam that rings a bell in the "Crime Doctors" head when it's reveled that he, Dr. Sam, got a note to meet him, his killer, outside the summer carnival or fair. It was at the fair that he and everyone in town, including Dr. Ordway, were at. Finding the note on the murdered Dr. Sam with his killer in to much of a hurry to get away, or just too absent-minded to grab and destroy it, turned out to be the evidence that in the end hung him! Not that Dr. Sam's killer wrote it but*****SPOILERS*****that he needed someone else to write it for him.
Dr. Ordway take his life in his hands in this murder mystery by getting both Dr. Sam & Beacheys killer in a position where he can make Dr. Ordway his next victim. The "Crime Doctor" was more then ready for mysterious killer in alerting to towns sheriff old man Akers, Clem Bevans, and the local townspeople to come to his rescue. Dr. Ordway slug-fest with the crazed killer, after failing to poison Dr. Ordway, just about to split Dr. Ordway's head open with a shovel.
Arrested and facing life or even the electric chair, if convicted in both Dr. Sam & Bencheys murder, the killer tries to be real cute by faking that he's nuts. The killer acts as if he's trying to catch or swat invisible flies or horseflies in his cell thinking that would get him off on an insanity defense. It just happened that the "Crime Doctor" got his number and then tricks him into showing everyone watching that he's indeed sane. Dr. Ordway does this by showing that the killer thinking that he's acting insane is in fact really thinking and rational, in trying to show that he's indeed crazy, by falling right into the clever trap that Dr. Odway's set for him.
