Operation Underworld is dadly historical narrative non-fiction about one of the weirder alliances in a war full of weird alliances. In early 1942, as the United States entered the war and Nazi U-boats sank ships by the scores up and down the coast, security of the ports was a major concern. A naval reserve intelligence officer, Commander Charles Radcliffe Haffenden, with a unclear remit, limited resources, and immense personal daring, decided to do whatever it took to develop sources along the New York waterfront, and that meant the Mafia.

An immense amount of war material moved through the port of New York, and sabotage was the first major concern. The waterfront was intensely mobbed up, a network of territories and bosses all ruled by the iron code of silence the Mafia called omerta. Collaborating with the authorities was forbidden. Haffenden managed to convince a capo working out of a fish market, a beefy man by the name of "Socko" Lanza that it was his patriotic duty to help the Navy, and Lanza agreed, and also said that real cooperation required the approval of Charles 'Lucky' Luciano, the currently imprisoned head of the five families.

Haffenden sent word to Luciano, Luciano said yes out of a combination of patriotism and self-interest, and the partnership started up. It's military effects are mixed at best. Sabotage appears to be a largely overblown threat, with Nazi special agents bumbling their way into the hands of the FBI, and local radicals equally incompetent. Mafia-connected individuals provided intelligence for the landings in Sicily, as well as some on-the-ground help. Most key, supplies kept flowing through the ports without strikes or stoppages.

Neither of the participants got what they wanted out of the deal. Haffenden wound up thrown under the bus by the Navy, since he had greatly exceeded his authority and blemished their reputation. Luciano used Operation Underworld meetings as a cover for setting up his gambling syndicate, and while his sentence was commuted, he was deported to Italy and never returned to New York.

In one of those weird historical twists, Operation Underworld would likely have been completely buried, except Luciano was obsessed with the idea that New York Governor Thomas Dewey (of "Dewey Defeats Truman" fame) owed him favors, and Dewey commissioned an extensive report to clear his name, which didn't really do much, but set down thousands of pages of primary sources. These sources have been declassified since the late 1970s, and there are other books, but Black has added a novelistic flair, which adds interest to what is otherwise a rather vague and bureaucratic story that happens to involve the Mafia, but also isn't quite history.