He looked so desperate, so … driven. And on their way home after the all clear, he pulled Polly aside to say, “I’ll think of some way to get you out of here before your deadline. Both of you. I promise.”

The next night he met her outside Townsend Brothers after work. “Tell me about the buildup to D-Day,” he said.

“The buildup? But—”

“We don’t know for sure that Denys Atherton came through in March. Mr. Dunworthy may have rescheduled his drop.”

Or canceled it, she thought. Or his drop wouldn’t open, like Gerald Phipps’s, and he wasn’t able to come through.

“Or Atherton may have had to come through early like you did,” Mike said, “so he could be in place when the invasion buildup started.”

She shook her head. “That wouldn’t have been necessary. There were hundreds of thousands of soldiers pouring into the camps. He wouldn’t have been noticed at all.”

“Pouring in where?” he persisted. “Where was the buildup?”

“Portsmouth, Plymouth, Southampton. But it covered the entire southwestern half of England,” she said, and then was sorry. She shouldn’t have made finding him sound so difficult. She didn’t want Mike to decide it was hopeless and do something rash like go to Eileen’s drop, Army or no Army. Or to Saltram-on-Sea to blow up the gun emplacement on his drop.

But he didn’t speak of doing either. And the next night when he told them he’d thought of a plan, it involved nothing more than taking turns checking Polly’s drop and composing additional personal ads to be put in the newspapers.

“But we already did that,” Eileen said, “and no one answered.”

“These aren’t messages to the retrieval team,” Mike said. “They’re messages to Oxford.”

“But how can we send messages to the future unless we find another historian?” Eileen asked. “We don’t know where Mr. Bartholomew’s drop is.”

“We send them the same way we sent the messages to the retrieval team. Remember those messages you told us about, Polly, that British Intelligence put in the newspapers to fool Hitler into thinking the invasion was coming at Calais instead of Normandy?”

“The wedding announcements and letters to the editor?”

“Yes. And there’s the Verlaine message and the other coded messages they sent out over the BBC to the French Resistance.”

“But those messages weren’t to the future,” Polly said.

“No, but they made it to the future. After World War II, historians went through all the newspapers and all the radio recordings and telegrams of the time, looking for clues to what had happened, and they found the Fortitude South and BBC messages.”

“But they were looking through the 1944 newspapers,” Polly said. “Why would they look for messages in 1941 newspapers?”

“Because we’re in 1941. They’ll be trying to find out where we are,” he said, “and we’re going to tell them.”

It won’t work, Polly thought. If they were looking for messages, they’d already have found the ones the three of us sent to the retrieval team, and they’d have been in Trafalgar Square or at the Peter Pan statue.