The cab sped off. Abbington-Westlake gave an upper Fifth Avenue address and settled in for the ride. At 59th, the cab suddenly swerved into Central Park. He rapped his stick on the window.

“No, no, no, I’m not some tourist you take around the park. If I wanted to drive out of my way through the park, I would have instructed you to go out of the way through the park. Return to Fifth Avenue immediately!”

The driver slammed on the brakes, throwing Abbington-Westlake off his seat. When he recovered, he found himself glaring into the cold eyes of a grim-visaged Isaac Bell.

“I warn you, Bell, I have friends who will come to my aid.”

“I will not deliver a well-deserved punch in your nose for selling me down the river to Yamamoto Kenta if you answer a question.”

“Was that you who killed Yamamoto?” the English spy asked f earfully.

“He died in Washington. I was in New York.”

“Did you order his death?”

“I am not one of you,” said Bell.

“What is your question?”

“Whoever this freelance spy is, I believe he is acting strangely. Look at this.”

He showed Abbington-Westlake the note. “He left this on the body of my detective. Why would he do such a thing?”

The Englishman read it in a glance. “Appears to be sending you a message.”

“Would you?”

“One does not indulge in childish exercises.”

“Would you kill my man for revenge?”

“One does not indulge in the luxury of revenge.”

“Would you do it as a threat? Believing it would stop me?”

“He should have killed you, that would put a stop to it.”

“Would you?”

Abbington-Westlake smiled. “I would suggest that successful spies are invisible spies. Ideally, one copies a secret plan rather than stealing it so one’s enemy never knows that his secret was stolen. Similarly, if an enemy must die, it should seem to be an accident. Falling debris at a work site might crush a man without raising suspicion. A hatpin piercing his brain is a red flag.”

“The hatpin was not in the newspapers,” Bell said coldly.

“One reads between the lines,” the Englishman retorted. “As I told you at the Knickerbocker, welcome to the world of espionage, Mr. Bell. You’ve learned a lot already. You know in your gut that the freelance spy is not first and foremost a spy.”

“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?”