R. Austin Freeman 
Uttermost Farthing 
A Savant’s Vendetta

Humphrey Challoner is an eccentric collector and amateur scientist who has put his vast fortune to work funding his many unusual interests and obsessions. When his beloved wife is murdered, Challoner decides to take the law into his own hands and dispense justice on his own terms. The Uttermost Farthing provides an interesting view of how far one man will go to right a wrong.