Trent's Last Case

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.