“He?” he said blankly.

“When he ran his bicycle into you,” the first girl said, and it was only then that he realized he’d been knocked down by a bicyclist. He looked on down the street to see the bicycle wobble and swerve and then crash into the curb, spilling its rider onto the pavement and clattering onto its side.

The girls saw the bike crash, too, but they paid no attention, even though it looked like the rider had taken a much worse fall than Mike had. They were busy picking Mike up. “Are you injured?” the first girl asked anxiously, putting her hand under Mike’s arm to help him up.

“I think he only clipped me,” Mike said.

The other was standing with her hands on her hips, staring at the rider, who was getting slowly to his feet. “He shouldn’t be allowed on the streets,” she said, annoyed.

“Do give us a hand, Mavis,” the first one said to her, and Mavis came over to take Mike’s other arm. Mike stood up, more or less. “Are you certain you’re not hurt?” she asked.

“I don’t think so,” he said, taking stock. His knee was beginning to throb, but he was able to put weight on it, so it wasn’t broken or sprained, and it and his hands had struck the pavement first. He flexed his fingers. “I think I’m fine. Anyway, nothing’s broken. I should have been looking where I was going.”

“You should have?” Mavis exploded. “He should have. It’s the third time he’s knocked someone down this week! Isn’t it, Elspeth?”

Elspeth nodded. “He nearly killed poor Jane on her way to the Park last week.” She glared at the rider, who was righting his bicycle. He got on and rode off down the street, apparently unharmed. “Watch where you’re going!” she shouted after him, to no effect. He didn’t even look back.

“You’re certain you’re all right?” Mavis was asking. “Oh, you’re limping.”

“No, that isn’t from—”

“I knew he’d end by injuring someone,” Mavis said angrily. “He never watches where he’s going.”

“My foot’s not hurt,” Mike said, but neither girl was listening.

“He’s an absolute menace,” Mavis said angrily. “He should be forbidden from riding a bicycle.”

Elspeth shook her head. “He’d only begin driving his car again, and that would be even worse,” she said. “Turing’s a wretched driver.”

In wartime the truth is so important it must be accompanied by a bodyguard of lies.

WINSTON CHURCHILL, IN A SPEECH AT BLETCHLEY PARK

London—November 1940

POLLY AND EILEEN WAITED TO MAKE SURE MIKE’S TRAIN actually left for Bletchley Park, and then Eileen went to Whitechapel to return Alf Hodbin’s map. “I told them I’d post it to them, but I promised Theodore Willett I’d go see him, so I may as well run it by. And I want to talk to Alf. I got the feeling last time that he and Binnie are up to something.”

“Like what?” Polly asked.

“I’m not certain, but knowing the Hodbins, it’s something illegal. There weren’t any Nazi child spies, were there?”