“This one might do, Dilly,” Mr. Bradshaw interrupted, and Beth shrank as every eye in the hall turned to her. “I was going to put her into administration, but you might give her a trial first if you’re shorthanded.”

“Eh?” The White Knight turned with a glare. His eyes behind the glasses raked Beth, and she stood frozen. “You’re good with languages?”

“No.” Beth had never felt so shy, slow, stilted, and stuck in her life. From Commander Denniston’s grateful glance at Bradshaw, she knew perfectly well this was a diversion—chucking her into the line of fire to avert further shouting. Her face burned.

“What about linguistics? Literature?” the White Knight fired off. “Even maths?”

“No.” Then for some reason, Beth whispered, “I—I’m good at crosswords.”

“Crosswords, eh? Peculiar.” He pushed his glasses further up his nose. “Come along.”

“Miss Finch hasn’t got her official pass yet—”

“Has she signed the Act? Let her start. As long as you can shoot her if she blabs, who cares about the pass?” Beth nearly fainted. “I’m Dilly Knox. Come with me,” the White Knight said over his shoulder, and led her through the looking glass.

What is this place? Trailing after Mr. Knox as he limped out of the mansion toward what appeared to be a converted stable block, Beth couldn’t stop Lewis Carroll from chaining together in her whirling head. Her brain did that sometimes, went flashing down an association and kept linking others to it to make a pattern. Glancing up at the bronze-faced clock mounted on the half-timbered upper tower, she wouldn’t have been surprised to see the hands running backward. Why hadn’t Osla and Mab warned her? But they couldn’t say anything; they’d signed an oath . . . and now, so had Beth. Whatever happened here now, she wasn’t going to be able to tell her mother a thing.

Her stomach swooped. Mother is going to be furious.

Beyond the old stable yard was a compact single-storied block: three brick cottages joined together in a single whitewashed unit, with two doors. Mr. Knox struck open the rightmost. “We work here,” he said, beckoning Beth through a corridor. “It’s like a great factory, the rest of BP. Here’s where we do proper cryptography.”

Cryptography, Beth thought. I now do cryptography.

There was no Wonderland inside the desk-crammed, chalk-dusty room where he led her, just five or six women hard at work—short and tall, pretty and plain, looking as young as eighteen or as old as thirty-five in their jumpers and skirts. None looked up. “Were you shouting at Denniston again, Dilly?” an older woman with straw-fair hair asked.

“I was sweet as a lamb. I told him just last week that he couldn’t—”

“Dilly darling, no.” The woman was manipulating a set of cardboard strips in a pattern Beth couldn’t follow. “You didn’t tell Denniston anything last week.”

“Didn’t I?” He scratched his head, all his earlier rage seemingly dissipated. “I rather thought last week one had said the right thing . . .”

“One hasn’t said anything before today. One hasn’t spoken to Denniston at all for two weeks.” The straw-haired woman exchanged smiles with the younger girls.

“That would explain why he looked so puzzled.” Mr. Knox shrugged, turning back to Beth. “Meet my ladies.” He gestured to the room. “Dilly’s Fillies, they call ’em at the mansion. Utter rot, but around here, if it rhymes, it sticks. Ladies, meet—” He looked at Beth. “Did you tell me your name?”

“Beth Finch—”

“Ladies, Beth Finch. She’s . . .” He trailed off, patting his pockets. “Where are my glasses?”

“On your head,” at least three of the women said, without looking up.

He located his spectacles and draped them over his nose. “Take a desk,” he said, waving at Beth. “Have you got a pencil? We’re breaking codes.”

He flung himself down at a desk by a window, fumbling for a tin of tobacco and seemingly forgetting Beth’s existence. Most of the girls went right on working as though this were a perfectly normal state of affairs, but the small woman with the straw-fair hair rose, extending a hand.

“Peggy Rock.” One of the older women, thirty-five or thirty-six, a plain face that sparkled with intelligence. “I’ll show you the ropes. That’s Dillwyn Alfred Knox,” she said, pointing to the White Knight, “and he was breaking German codes back in the Fourteen–Eighteen War. Dilly’s team here researches the stuff that has to be lockpicked rather than brute-force assembly-lined through the other huts. Right now we’re working the Italian naval Enigma—”

“What’s Enigma?” Beth said, utterly bewildered.

“The machine the enemy uses to encrypt most of their military traffic,” Peggy said. “Italians and Germans, naval traffic and air traffic and army traffic, and every cipher has a different setting. The machine has, well, let’s just say a dizzying number of setting combinations, and the settings change every day, so that should make whatever they encrypt with Enigma unbreakable.” She gave a small smile. “Not as unbreakable as they think.”

Did Osla know all this? Beth wondered. Did Mab?

“We tend to get a bit more of the big picture here than the others at BP,” Peggy added as if reading her mind. “They’re such fiends for compartmentalization here—most people just see the bit in front of them, and maybe they put a bit together from what they see going in and out of the other huts, but that’s all—”

“Utter rot.” Dilly’s voice floated from his desk. “I want my girls to have a large, unhampered range. You benefit from seeing the whole picture, not bits and pieces of it.”

“Why?” Beth asked.

“Because we do the tricky part.” Peggy Rock spread her hands. “The traffic gets registered and logged elsewhere, and once it’s broken it gets translated and analyzed—but we do the important bit in the middle. The prying-it-all-open bit, every message individually. We use a technique called rodding to identify the start position of the message as seen through the window indicator setting. Let me show you—”

“I won’t understand it,” Beth blurted out. “I’m not clever, you understand? I can’t do—” Rodding. Cryptography. This. Her chest was tight; her breath heaved; the walls pulsed around her. It paralyzed her to stray even a few steps outside her usual routine, and here was a whole new world. Any moment now she was going to panic. “I’ll hold you back,” she insisted, close to tears. “I’m too stupid.”

“Really?” Peggy Rock looked at her calmly, fanning out a handful of those curious cardboard strips like a winning hand of cards. “Who told you that?”

Chapter 11

I miss you, Os. I miss you a shocking lot, to be honest.

Philip’s handwriting was clear, no flourishes. Seeing it always made Osla’s heart thump. Shut up, heart, she scolded.

“Mrs. F’s really having a go.” Mab was eavesdropping unashamedly downstairs, head poked into the dark landing. Beth’s first shift at Bletchley Park had been today, right after her interview, and Mrs. Finch had been twitching. Now Beth was back, not that they could hear her. Just her mother’ s insistent voice, quoting something from the Bible about For son treats father contemptuously, daughter rises up against her mother—

“Should we pop down?” Osla looked up from the bed where she was curled rereading Philip’s old letters. “Interject various patriotic things like ‘Let your daughter work, you meddling cow, there’s a war on’?”

“We’ll only make things worse,” Mab said. “Mrs. F’s on Ezekiel now.”

Gnawing her lip, Osla turned back to Philip’s salt-stained letter from May. Being transferred to the Kent when I was just getting used to the Ramillies; that was a bit of a letdown. None of the ratings here are all that keen on having royalty aboard, even third-rate royalty like me. You should have seen the eyes rolling when I first came on. Whisper is we’re off to hunt for some action soon. Don’t worry, darling girl—

He hadn’t seen any action with the Kent, but now he was being transferred again, to her sister ship—who knew where it would take him? Osla shivered. U-boat wolf packs roaming the sea, and of course he'd want to charge right into the thick . . .

“Here she comes,” Mab whispered as Beth’s footsteps came up the stairs. Osla slid off the bed, tucking Philip’s letter into her copy of Through the Looking-Glass. When Beth appeared on the landing, Osla and Mab whisked her into their room and shut the door.

“Well?” Osla checked Beth’s arms—no bruises, thank goodness. “Your mother can’t refuse, surely! You know, I thought it might take longer when I put your name in. Sometimes the vetting takes weeks—”

“So you did recommend me.” Beth’s voice was flat.

“Yes.” Osla smiled. “I thought you might need an excuse to get out of the house—”

“You thought.” Osla had never heard Beth interrupt anyone, but she cut Osla off now. Her cheeks flared scarlet. “You know what I think? I think I wanted to be left alone. I think I want my mother not to be angry with me, or make me hold the Bible up for twenty minutes. What I don’t want is a job with strange people doing work I don’t understand.”