Mr. Pottermack's Oversight

On a sweltering July afternoon, a man in prison garb escapes through dense foliage, eventually disguising himself as a beachgoer named Mr. Pottermack. As he navigates his precarious new life, a blackmailing threat emerges, leading to a violent turn of events and the dire need to remain hidden. With the astute Dr. Thorndyke suspecting foul play, a suspenseful cat-and-mouse chase ensues, as both the detective and Pottermack strive to uncover or conceal the revealing truth in this inverted mystery first published in 1930.