Her eyes danced, spiteful. Beth reared back and spat on the front of her apron.

A needle pricked. “Just wait, you nasty little thing,” the matron said as soon as the doctor left. “When they get you under the scalpel—”

“When?” Beth hissed, but the matron was gone, the world sliding away into smoke and mirrors. Beth’s veins felt unclean, as if her blood had been greased. She found herself weeping at some point and forced the tears away. Tears would wear her mind down like water on stone, and her mind was all she had.

I break codes. I eat secrets. Enigma was no match for me—neither is this place.

Breathe in, breathe out. Ignore the numbness of her trapped hands. Think of something else, not scalpels and spiteful matrons and oblivious doctors with their unfair punishments.

Unfairly punished . . . Beth’s drugged memory turned up something long forgotten: Osla hauled up by Commander Travis at BP, raked over the coals about Prince Philip’s Nazi relatives, interrogated about what Osla had guessed were some missing decrypted messages from Hut 3. When had that been, June ’42? If someone had snatched files, they could easily have reported beautiful, highly visible Osla, who had sauntered over from Hut 4 on routine business and diverted attention from the presence of a traitor.

Who? Beth thought. Back to that again, endlessly turning over old memories, hoping for some fresh insight—but none of her ISK colleagues had ever worked in Hut 3.

So don’t focus on the where, Beth thought. Focus on the when. June of ’42 . . .

Peggy Rock had returned to Bletchley Park from her breakdown that same month. Peggy, the cleverest woman Beth knew. Had there really been a breakdown? Or had she been . . . somewhere else? Meeting someone, passing information?

Beth had weighed Peggy’s name before on her list of suspects and always cringed from the thought. Peggy a traitor? Fair-haired, brilliant Peggy who had shown her how to rod?

But Peggy worked in ISK. She had disappeared and been gone for months. She had returned to work, Dilly’s best codebreaker aside from Beth. A woman as clever as Peggy could have found a way to walk into Hut 3 and out again with a file, surely. And with Dilly no longer keeping an eye on his section’s day-to-day routine . . .

Peggy. Yes, she might be the one.

Or any of Dilly’s team. Dear friends all, because Beth had made friends almost exclusively inside Knox’s section. Except for Osla and Mab, who now hated her.

What a cruel twist of fate that her friends were all suspects, and her enemies were the only ones she was sure of.

Come on, you two, Beth thought throughout the endless afternoon, canvas-bound and helpless. Come through.

York

Mab dropped her teaspoon. “You want us to go where?”

“To Clockwell, to see Beth.” Osla saw they were getting glances from the other patrons of Bettys tea shop, and no wonder—two well-groomed women in New Look billows of skirt, dagger eyed, going at each other over the teacups for the past half hour. “Try not to look so hacked off, will you? We’re attracting attention.”

Mab bared all her teeth in a smile, violently stirring her tea. “I am not going to a madhouse.”

“You’re willing to leave her there, because you’re afraid?” Reverting to whispering, making sure no one was walking past. “When she may be perfectly sane, and there may be a traitor who betrayed Bletchley Park—who betrayed all of us who worked there—walking free? Now, that really takes the biscuit, darling.” Osla gave Mab a withering look. “I knew you were a ruthless cow, but I didn’t think you’d become a coward.”

“I’m not afraid, you featherweight gossip-page hack.” Mab reverted to whispers, too. “I’m pointing out that we could be breaking the law by contacting her at all.”

“We would also be breaking the law if we allowed the secrecy of our work to be compromised.” Osla leaned forward. “I may be a featherweight gossip-page hack now, but I take my oath seriously.”

“But you can’t possibly entertain the notion that someone at BP—”

“Yes, I can. Remember the time I was hauled into Travis’s office and accused of lifting files from Hut 3? I ranted to you and Beth about it.” The rifled Hut 4 box files, too . . .

Mab fiddled with her strand of black pearls. “So we report this to someone higher up. Someone unconnected with Beth’s section.”

“No one is going to take it seriously, because they think Beth’s gone potty. But we lived with her for years, and we know her better than anyone. If we see her in the flesh, put the question to her ourselves”—However we can make that happen, Osla thought—“we’ll know if she’s crazy. We’ll know if she’s lying.”

Mab spoke very low. “And what if we don’t think she’s lying?”

A long silence.

“We’ll think of something.” Osla pushed her teacup away. “Perhaps there’s something my godfather could do. Pull strings—”

“Or you could ring Philip,” Mab suggested. “It must be nice having the future royal consort in your address book. He’s got to be worth a ring on the telephone, even if he came up short as far as rings on the finger.”

“Mention Philip again,” Osla snapped, “and I’ll cram those pearls up your nose until you are sneezing nacre, Queen Mab.”

“You aren’t exactly endearing yourself to me, considering you want my help.”

“I don’t want your help, you blithering bitch. I need it. I need another pair of eyes on Beth to figure out if she’s talking straw or gold.” Osla began tugging on her gloves. “The eleven oh five leaves tomorrow morning, and it stops two miles from Clockwell. I plan to be on it.”

“Don’t count on me joining you.” Mab finally broke down and took a scone, reaching for the butter dish.

“No one could ever count on you for anything, Mab. Break form for once, why don’t you.” Osla rose, smiling sweetly. “Not too much butter, darling. Watch that waist! Right now, it’s all you’ve got going for you.”

Five Years Ago

June 1942

Chapter 40

* * *

FROM BLETCHLEY BLETHERINGS, JUNE 1942

* * *

Boffins and gents, stop trying to peek into the hut with all the machine racket going on inside. It is just a rumor that the Wrens sometimes strip down and work in their knickers.

* * *

Job’s up!”

It was always a moment, Mab reflected, when a proper stop was logged on one of the bombe machines—when all the checks came back and it wasn’t a mistake that had stopped the drums’ whirring, but success. Who knew what might come from the bombe’s latest break? Maybe intelligence important enough to go straight to Churchill’s desk. Ever since his visit, Mab had felt a bit proprietary about the prime minister. He wasn’t just Britain’s PM, he was her PM.

“Strip down,” Wren Stevens sighed as she and Mab began unplugging the great wired back of the machine. “I wish we could strip down.” They’d finally moved from windowless, claustrophobic Hut 11 to new-built 11A, which had an actual air-conditioning unit—but the unit was on the fritz, as the Yanks would say, and the summer heat inside the hut was overwhelming. Mab felt sweat running down her back, and the Wrens in their smart brass-buttoned uniforms had it even worse.

“Well, why don’t we?” she replied with a grin. “Who’s going to see us?” The Wrens laughed uncertainly, but Mab was fizzing along, carefree and happy. She was going to see Francis tomorrow—they’d have three days together in Keswick. “Let’s have a bit of mischief!” She yanked her sweaty frock over her head and her gummy slip after it, hanging them on a nail. She stretched her arms, standing in her knickers and brassiere. “Much better.”

“Right, I’m with you.” Stevens began unbuttoning her uniform, and soon they were all stripping down and going back to man their machines in their unmentionables. Mab carefully tweezed the tiny drum wires apart, plugged up the back for a new menu, and gave Aggie a pat. “Ready to go, you cranky cow.” She set it in motion, for once not minding the clacking drone. There were many more bombe machines now besides these—so much traffic poured through BP, the handful of bombes here couldn’t possibly cope. And it would be dangerous, anyway, to keep all the machines in one place where a single Luftwaffe strike could knock out Britain’s entire decoding capacity. The Wrens said that there were stations in Adstock Manor, Wavendon, and Gayhurst now—Mab wondered if any of the Wrens at those stations were on duty in their knickers.

The shift was about to turn over, and the operators shrugging back into their clothes, when a young Wren slid through the door with a miserable look. “Why the long face?” Mab asked.

“Does anyone know Wren Bishop?” the girl blurted. “Stationed at RAF Chicksands?”