U-boat

Known within their own ranks as “U-boats,” they survived under seemingly impossible conditions thanks to the ingenuity and courage of Maltzan and others like her.

The German U-boat force maintained a fearsome reputation.

For the most part, however, “Wolfpack” chronicles the misery, failure and deaths of U-boat crews.

As America entered World War II, New York City was threatened by prowling U-boats off the coast and Nazi spies lodged in Manhattan hotels.

Once the Navy had cleared the coast of U-boats, writes Mr. Wallace, New York became “the most spectacular war port in the world.”