Product: The Hidden Hand of Death (The Jack Ryder Mysteries Book 1)
It is early in 1942. The war with Germany has just begun. Jack Ryder, who calls himself a fixer rather than a detective, wanders the darkest nights to his office in a back booth at an all-night diner. Ryder is famous for killing members of the mob who have crossed their bosses by hurting innocent people. Ryder also helps ordinary people in trouble. 
 
An enemy—a homicide detective—comes to hire Ryder to find the detective’s missing sister. Ryder also gets involved in going up against some Nazis in New York and saving a woman on the run from gangsters.

Search query: historical fiction book series
Relevance: Exact