Trent's Last Case by E.C. Bentley

On Wall Street, the mere mention of the name Sigsbee Manderson is enough to send a stock soaring—or bring it tumbling back to earth. Feared but not loved, Manderson has no one to mourn him when the gardener at his British country estate finds him facedown in the dirt, a bullet buried in his brain. There are bruises on his wrist and blood on his clothes, but no clue that will lead the police to the murderer. It will take an amateur to—inadvertently—show them the way.

Cheerful, charming, and always eager for a mystery, portrait artist and gentleman sleuth Philip Trent leaps into the Manderson affair with all the passion of the autodidact. Simply by reading the newspapers, he discovers overlooked details of the crime. Not all of his reasoning is sound, and his romantic interests are suspect, to say the least, but Trent’s dedication to the art of detection soon uncovers what no one expected him to find: the truth.

Delightfully irreverent yet ingeniously plotted, Trent’s Last Case is widely regarded as a masterwork of the mystery genre.