Hulbert Footner 
Taken for a Ride [EPUB ebook] 

Dr. Portal brought a baffling case to Mme. Storey: Dr. Edgar Mc Comb was found shot dead in his office. It attracted very little notice simply because there were no sensational circumstances. Now that a month has passed, it remained a mystery. The police had nothing to go on. No clues of any sort. Nobody saw the assailant enter or leave the building; no fingerprints were found in the room save those of the doctor himself. And even more baffling, no possible motive for the crime had been unearthed.