Publisher's Synopsis
The Red Thumb Mark Dr John Evelyn Thorndyke's first case. The doctor-turned-lawyer immerses himself in the mystery of missing jewels stolen from the vault of Mr John Hornby and his firm. Only four people have keys to the vault, and one of the men is arrested. Thorndyke and his assistant Dr Jervis are not convinced the man is guilty, however, and set out to prove his innocence. Their best lead is a clue: a bloodied red thumb print left in the vault.