The Red Thumb Mark

Doctor Thorndyke, aided by an old university acquaintance, Doctor Jervis and his trusted laboratory assistant Polton, is tasked with the challenge of proving Reuben Hornby innocent of having stolen a number of expensive diamonds from his uncle’s business’s safe. The safe was not tampered with and the only people who could have accessed the safe key at all are Reuben, his uncle John and his cousin Walter. Yet what points Reuben is that inside the safe there are drops of blood and a memo note with a bloodied thumb print which appears to be his own; a comparison made using a record of Reuben’s thumb print in a Thumbograph. Prior to Reuben’s trial the narrator, provides information on Jervis actions and it is through him that we find out more about Reuben’s family. Though it seems that in the case of one family member, Juliet Gibson, his views are inevitably romantically biased. Eventually the day of the trial emerges and it remains to be seen whether Thorndyke can find out who took the diamonds.