The Gangster (Isaac Bell, #9)

It is 1906, and in New York City, the Italian crime group known as the Black Hand is on a spree: kidnapping, extortion, arson. Detective Isaac Bell of the Van Dorn Agency is hired to form a special Black Hand Squad, but the gangsters appear to be everywhere so much so that Bell begins to wonder if there are imitators, criminals using the name for the terror effect. And then the murders begin, each one of a man more powerful than the last, and as Bell discovers, to his dismay, the ultimate target may be the most powerful man of all.