“Blow our agents’ cover,” Cess said.

Tensing nodded. “And jeopardize any future deception plans. Which is equally unacceptable.”

“So we need to deceive the Germans into thinking their rockets fell where they didn’t,” Cess said. “How do we do that? Create dummy bomb sites?” Ernest had a sudden vision of an inflatable heap of rubble. He suppressed a smile.

“We did consider that,” Tensing said. “Already-existing rubble moved to another site was used effectively in North Africa. But one of our science chaps has come up with a better plan.”

He unrolled a map of southeastern England on the table. It was marked with a number of red dots, which Ernest assumed were V-1 incidents. “We know from our intelligence that in the trials at Peenemünde, the V-1 tended to fall short of the target, and, as you can see from the map, that problem has continued, with the largest number of bombs falling here”—he pointed at an area southeast of London—“rather than in the center of the city.”

“Which is what the Germans are worried about,” Ernest said, “and why they’re demanding the information.”

“Yes, but it’s in our interest to keep them from correcting the trajectory, to see to it that the V-1s continue to fall short.”

“So you switch the bombs that fall short for the ones that reach their target,” Ernest said.

“Exactly.”

“What?” Cess said, looking thoroughly confused. “How can you switch bombs?”

“Bomb A falls in Stepney at nine o’clock at night,” Ernest explained. “Bomb B falls on Hampstead Heath at half past two in the morning. Our agent tells the Germans bomb A was the one that fell at half past two.”

“In Hampstead,” Tensing said. “And the Germans think it overshot its target, and they shorten its trajectory.”

“Which makes the next one fall short,” Cess said, catching on. “But how do we ensure it falls somewhere where it won’t do any damage?”

“Unfortunately, we can’t, but we can increase the chances of a rocket falling in woods or a field—”

“Or a pasture,” Cess said. “Worthing, this is your chance to eliminate that bull that caused you so much trouble.”

Tensing went on as if Cess hadn’t spoken. “But we can increase the chances of their landing in a less-populated area than central London.”

That’s why you were so eager to point out the thousands of lives we saved, Ernest thought. Because now we’re going to start killing people.

“The retargeting will allow us to provide false information without arousing suspicions regarding our double-agents,” Tensing said. “And to significantly lower the number of casualties.”

And kill people who wouldn’t otherwise have died, Ernest thought. “So what’s our job?” Cess asked. “We’re to match up the bombs?”

“No, I need you two to provide corroboration,” Tensing said, and handed Ernest a photograph of a pile of rubble. It was impossible to tell what it had been from the tangle of bricks and lengths of wood.

“This happened in Fleet Street Tuesday afternoon at 4:32 P.M., but we’re telling the Germans it’s Finchley. The high level of destruction makes substitutions comparatively easy. We’ve told the newspapers they’re not to print any photographs or information about rocket attacks without our authorization.”