In The Terrible Hours, Maas reconstructs the harrowing 39 hours between the disappearance of the submarine Squalus during a test dive off the New England coast and the eventual rescue of 33 crew members trapped in the vessel 250 feet beneath the sea. It's also the story of Momsen's triumph. Under the worst possible circumstances, Momsen led a successful mission and helped change the future of undersea lifesaving. Not only has Maas written a carefully researched and suspenseful tribute to a true hero, in the process he has salvaged a long-forgotten, riveting piece of American history.