“He doesn’t think like a spy,” said Bell. “He thinks like a gangster.”

“Then who better to catch a gangster than a detective? Good day, sir. May I wish you happy hunting?” He climbed out of the cab and walked toward Fifth Avenue.

Bell hurried back to the Hotel Knickerbocker and corralled Archie Abbott.

“Get up to the Newport Torpedo Factory.”

“The Boston boys are already-”

“I want you. I’m getting a strange feeling about that attack.”

“What kind of feeling?”

“What if it wasn’t sabotage? What if it was a robbery? Stay there until you discover what they took.”

He walked Archie to the train at Grand Central and returned to the office, deep in thought. Abbington-Westlake had confirmed his suspicions. The spy was first and foremost a gangster. But he couldn’t be Commodore Tommy. The Gopher had lived and fought within the narrow confines of Hell’s Kitchen his whole life. The answer must lie with Louis Loh. He could be the tong. He could even be the spy. Perhaps that was what he had noticed was different about Louis: he acted like he had a purpose. It was time to put the question to him.

Bell collected Louis Loh from the Brooklyn Navy Yard brig late at night and handcuffed his wrists behind his back.

Loh’s first surprise came when instead of putting him in a truck or an auto, Bell walked him toward the river. They waited at the water’s edge. Hull 44 loomed behind them. The wind carried the sounds of ship engines, slatting sails, whistles, and horns. Blacked out but for running lights, Lowell Falconer’s turbine yacht Dyname approached in near silence.

Deckhands guided Bell and his prisoner aboard without speaking a word. The yacht backed into the river and headed downstream. It went under the Brooklyn Bridge and passed the Battery and picked up speed on the Upper Bay.

“If you’re planning to throw me overboard,” Louis Loh said, “remember I know how to swim.”

“Wearing those manacles?”

“I assumed you would remove them, being above torture.”

The helmsman increased speed to thirty knots. Bell took Loh into the darkened cabin, where they sat in silence sheltered from the wind and spray. Dyname crossed the Lower Bay. Bell saw the lightship flash by the porthole. When Dyname’s bow rose to the first Atlantic comber, Louis Loh asked, “Where are you taking me?”

“To sea.”

“How far to sea?”

“About fifty miles.”

“That will take all night.”

“Not on this ship.”

The helmsman opened her up. An hour passed. The turbines slowed, and the yacht settled down. Suddenly it bumped hard against something and stopped. Bell took Louis’s arm, checked that he hadn’t jimmied open the cuffs, and led him out on deck. Silent deckhands helped them onto the wooden deck of a barge. Then Dyname wheeled about and raced off. In minutes, all to be seen of her was the fiery discharge from her stack, and soon she vanished into the night.

“Now what?” asked Louis Loh. Creamy whitecaps shone in the starlight. The barge rolled with the movement of the sea.

“Now we climb.”

“Climb? Climb what?”

“This mast.”

Bell directed Louis’s gaze up the cage mast. The airy structure rose so high that its swaying top seemed to brush the stars. “What is this? Where are we?”

“We’re on a target barge anchored in the U.S. Navy Atlantic Firing Range. Test engineers have erected on the barge this one-hundred-twenty-five-foot cage mast, the latest development in dreadnought spotting masts.”

Bell climbed two rungs, unlocked Louis’s right cuff, and locked it around his own ankle.

“Ready? Here we go.”

“Where?”

“Up these ladders. When I raise my leg, you raise your arm.”

“Why?”

“There’s a test scheduled for dawn to see how the cage mast fares in battle conditions when bombarded by 12-inch guns. Any spy worth his salt would give his eyeteeth to watch. Let’s go.”

It was long climb to the spotting top, but neither man was breathing hard when they reached the platform. “You are in excellent condition, Louis.” Bell removed the cuff from his ankle and locked it to the tubing that formed the mast.

“Now what?”

“Wait for dawn.”

A cold wind sprang up. The mast swayed as it sighed aound the tubing.

At first light, the silhouette of a battleship took shape on the horizon.

“New Hampshire,” said Bell. “You recognize her, I’m sure, by her three funnels and old-fashioned ram bow. You will recall that she carries 7- and 8-inch guns in addition to four 12s. Any minute now.”

The battleship emitted a red flash. A five-hundred-pound shell roared past like a freight train. Louis ducked. “What?” he screamed. “What?” Now the sound of the gun rumbled their way.

Another flash. Another shell roared closer.

“They’ll have the range soon!” Bell told Louis Loh.

The 12-inch gun flashed red. A shell struck in a shower of sparks fifty feet below. The mast shook. Louis Loh cried, “You’re a madman.”

“They say this helix design is remarkably strong,” Bell replied.

More shells roared by. When another hit, Louis covered his face.

Soon there was enough light in the sky for Bell to read his gold watch. “A few more single shots. Then they’re scheduled to blast salvos. Before they finish up with full broadsides.”

“All right. All right. I admit I am tong.”

“You’re more than tong,” Isaac Bell replied coldly. He was rewarded by an expression of surprise on Louis’s ordinarily immobile face.

“What do you mean?”

“Sun-tzu on the art of war. If I may quote your countryman: ‘Be so subtle that you are invisible.’ ”

“I don’t know what you mean.”

“You told me on the train, ‘They think we’re all opium addicts or tong gangsters.’ You sounded like a man with a broader point of view. Who are you really?”

A salvo thundered. Two shells ripped through the structure. Still it stood, but it was swinging side to side.

“I am not tong.”

“You just told me you are. Which is it?”

“I am not a gangster.”

“Stop telling me what you aren’t and start telling me what you are.”

“I am Tongmenghui.”

“What is Tongmenghui?”

“Chinese Revolutionary Alliance. We are a secret resistance movement. We pledge our lives to revive Chinese society.”

“Explain,” said Isaac Bell.

In a rush of words, Louis Loh admitted that he was a fervent Chinese Nationalist plotting to overthrow the corrupt Empress. “She is strangling China. England, Germany, all Europe, even the U.S., feed on China’s dying body.”

“If you are a revolutionist, what are you doing in America?”

“Dreadnought battleships. China must build a modern fleet to fend off colonial invaders.”

“By blowing up the Great White fleet in San Francisco?”

“That wasn’t for China! That was for him.”

“ ‘Him’? Who are you talking about?”

With a fearful glance at the New Hampshire, Loh said, “There is a man-a spy-who pays. Not in money but in valuable information about other nations’ dreadnoughts. We, Harold Wing and me, pass it along to Chinese naval architects.”

“And you pay for it by doing his bidding.”

“Exactly, sir. Can we go down now?”

Bell knew this was a major breakthrough in the case. This was the freelance whom Yamamoto had tried to betray in exchange for a clean escape. Louis had gotten him close again.

“You are working for three masters. The Chinese Navy. Your Tongmenghui resistance movement. And the spy who paid you to attack the magazine at Mare Island. Who is he?”

Another freight train of a shell roared by. The structure trembled. “I don’t know who he is.”

“Who is your intermediary? How does he give you orders and information?”

“Mailboxes. He sent information, orders, and money for expenses in mailboxes.” Loh ducked another shell. “Please, let us go down.”

Across the water, sparkling in the first rays of sunlight, all the New Hampshire’s guns traversed toward the cage mast. “Here comes a broadside,” said Bell.