Within minutes, Bell had been hoisted to her main deck. Sailors escorted him to the base of a cage mast. He presented his map to the commander of the Sixth Squadron, a broadly grinning Rear Admiral Lowell Falconer, who seized it with his maimed hand, scanned it eagerly, and issued orders.

Bell said, “I’ll give the range boys a hand sorting out landmarks.”

A sailor half his age offered to help him climb the mast.

“Thanks,” said Bell. “I’ve been on one of these before.”

The New York’s 14-inch guns, designed by Arthur Langner, were mounted on special turrets that had been perfected by Langner’s acolytes. They could be elevated to extraordinary angles, vastly increasing the guns’ range. A fire-control system pioneered by Grover Lakewood’s team calculated the distance to the U-boat yard. Salvos thundered. High-explosive shells soared toward the distant coast.

By now, the tide had risen. German battle cruisers came boiling out of the harbor. They were fast and heavily gunned, but their armor was no match for the battleship New York’s, and they kept their distance until a brace of full-scale German dreadnoughts appeared next on the horizon. The sailors flanking Bell in the spotting top exchanged anxious glances.

The German dreadnaughts drew closer. The American kept bombarding its target.

At last, mountains of smoke marked the ruins of the U-boat yard. Falconer ordered what he described to Bell as a “prudent withdrawal.”

The German ships fired at extreme range, but the shells fell short and they were too late. With her original reciprocating engines replaced by the latest model MacDonald turbines, the New York left them in her wake.

As the American dreadnought steamed for the harbor of Scapa Flow in the Orkney Islands north of Scotland, Admiral Falconer invited Isaac Bell up to his private cabin just under the bridge. The U.S. Navy was dry, alcohol forbidden, but Bell had brought a flask, and they raised a glass to victory.

“This is one escapade that won’t appear in the history books,” Falconer told Bell, adding with a laugh that jealous British admirals would want Bell shot for upstaging them.

“Assure them,” smiled Bell, “that private detectives serve privately.” A ship’s carpenter knocked at the door and came in with a mallet and steel chisels. Falconer pointed at the builder’s plate, which read:

USS NEW YORK

Brooklyn Navy Yard

“Loosen that for me.”

“Yes, sir, Admiral!”

The carpenter chiseled around it, and when it was loose enough to pry from the bulkhead Falconer dismissed him. Alone with Isaac Bell, he peeled it away. Underneath it, raised characters welded to the steel read:

Hull 44

A WEEK LATER, Isaac Bell stepped off the train from Scotland and strode from Euston Station into London streets that looked weary from a long, long war.