The Venetian Key

Esteemed poison expert and medical adviser to the Home Office Sir Frank Tarleton finds himself drawn into a baffling mystery when he is visited by Sir Rowland Caythorpe, a man with a dubious past who fears he’s been poisoned. He soon learns that Caythorpe has been living under multiple aliases and is suspected by the police of running an illegal heirloom scheme.When Caythorpe’s niece calls in distress, claiming her uncle is trapped in a locked strong room, Tarleton rushes to the scene and discovers that he has died, possibly of heart failure but more likely as a result of foul play. The finger of suspicion points at those who stood to gain from his demise, including an American businessman, an English countess, an Indian princess, and a mysterious Mexican with a black beard.​​​​​​​With motives and secrets intertwined, Tarleton must unravel the threads of deceit to catch a cunning killer in this classic mystery which was first published in 1927.