Well, three and a half years was a long time.

She went back into the spirals of Rose, with something of an effort. Another hour limped by, working a potential crib that went nowhere. Beth sat back, eyes burning. “Why can’t I do this?” she heard herself whisper. “I’ve been going at it three days now, and there’s nothing. I can’t see it, the way I used to.”

“You will.”

“What if I don’t?” The words came out more despairing than she’d intended. “What if I can’t do it anymore?”

The thing that terrified her most—being locked out. That headlong rush of falling down the spiral into Wonderland, the world of letters and patterns that she’d walked in with such starry-eyed enchantment. Now she was banging on Wonderland’s gates until her fists bled, and everything remained locked. “How much of my mind did I leave inside those walls?” In the asylum, she had felt like the sanest one there. Now she was out, and she felt like a caged lunatic on display at a circus.

Harry’s big hand extended across the desk. Beth hesitated, then slid her bitten-raw fingertips into his palm. “Beth, you didn’t leave any part of your mind in that place.” His gaze was steady. “You can still do this.”

Her eyes blurred. He was warm, he was sane, and he believed in her. “Just—don’t treat me like I’m made of glass, Harry. I don’t have time to be broken right now.” Later, when Giles was caught, she’d let herself shiver and sob, feel all the damage the asylum had inflicted on her. Not now.

He squeezed her hand fiercely. “Then let’s get back to work.”

ANOTHER HOUR LATER, Harry was reading through boxing chains as Beth tried to follow a Dilly-esque thought about crabs and turnovers—and they both looked up as heels clattered in the corridor. “We’re absolutely dished,” Osla called, stamping into the library in her Buckingham Palace finery. “I’ve had no luck—Harry!”

“Hullo, gorgeous.” Harry rose, picking Osla up and out of her tiny patent-leather sling-backs. “I thought you’d be a duchess by now.”

“Even worse, darling. I’m engaged to a traitor, hadn’t you heard?” Osla turned to Beth as Harry set her back into her shoes, and Mab came into the room drying her hands on a tea towel. “I tapped all my godfather’s people in London, discreetly. No luck figuring out where we might turn up an Enigma machine.”

“Forget the Enigma machine for now. We still need a good break before we’ve got anything to feed into one.” Beth tugged at her frayed hair. “And we’re not getting there fast enough.”

“We need more brains on this.” Harry considered, fingers drumming. “I’ll ring the Prof; he’s in Cambridge on a sabbatical year. And my cousin Maurice, he worked on ciphers in Block F and he’s at the Crédit Lyonnais in London now—if they could come and put a few days in—”

“We can’t tell anyone about this,” Beth protested, panic beginning to lick through her veins. “We can’t trust—”

“We can.” Harry’s voice was quiet but very sure. “Beth, not many people have friends with intelligence work clearance and the absolute ability to keep secrets, but we do. Christ, do we ever. And we have a traitor loose and only a matter of days to catch him. Let’s put out the call to the ones we can trust.”

“We trusted Giles,” Osla pointed out.

“We have to trust that he’s the only bad apple in our acquaintance. We were picked. We were vetted. Overall, we have to trust that the process worked. Or else BP would never have thrived.”

A long pause. “What do we tell them?” Beth said, gnawing her thumbnail.

“That it’s BP business,” Mab said. “They’ll drop everything and come running, just like us. They spent an entire war doing that. It’s in their blood.”

“I’ll make up some more beds,” said Mrs. Knox, behind Mab. “Though I’ll wager there won’t be much sleeping. Goodness, how exciting.” Off she went, waving off help, and the others looked at one another.

“Assemble the Mad Hatters.” Osla headed for the telephone. “Invitations are being issued for one last absolutely topping Tea Party.”

Chapter 80

Knock knock. “Mr. Turing,” Mab greeted the dark-haired, round-shouldered man she’d seen ramble through BP followed by admiring whispers. “Thank you for coming at such short notice. Take this . . .” Folding his hand instantly round a cup of coffee. She’d learned something these last few days about dealing with cryptanalysts: point them at the coffee, point them at the problem, then get out of the way. “Work’s over there, in Dilly’s library.”

The Prof ambled to a seat opposite Beth and Harry, and Beth pushed over the stack of increasingly dog-eared messages. “Let’s see . . .” He began humming tunelessly, and Mab had to stop herself from snapping Stop that! She wasn’t going to snap at Alan bloody Turing just because she was missing her family and felt like biting someone’s head off. Mab had rung home that morning to say she’d be away another few days; the conversation with Mike had contained a lot of thorny silences and questions she’d had no choice but to evade. Think about that later, she advised herself.

Knock knock. “One of Dilly’s team?” Mab guessed, assessing the rosy-cheeked woman in the corridor.

“Phyllida Kent. Look, I’m happy to help, but I need some sort of authorization or proof that what you’re doing here is on the up—”

“We’re working on that. Come in, have a go . . .”

Knock knock. A brisk blond broom handle of a woman in a home-knit jumper came straight in and kissed Mrs. Knox on the cheek. Mab barely knew her except that she’d been another of Dilly’s team. I thought she was the traitor, Beth had said. Thank God she’s not, because she’s as good a codebreaker as me. “Peggy Rock, came as soon as I could. What have you got, and why do I need to get us authorization to investigate it?”

“We’re calling it Rose.” Harry pulled out a chair for her at what Mab was already thinking of as Boffin Island—the desk and two tables all pushed together, covered in decrypts, pencils, and rods. Like Puffin Island off the coast of Wales, where Mike had taken Mab on their honeymoon, but covered in weird cryptanalysts instead of weird birds.

“Hullo, you,” Peggy greeted Beth. “I thought you’d had a breakdown.”

“Frame-up,” Beth said succinctly.

“Bastard.” Peggy surveyed everything, hearing the rest of Harry’s explanation. “All right, let me work up some official cover for all this through my office. Semi-sanctioned operation investigating remaindered code for purposes of research and security, maybe.” That, Mab thought, ought to satisfy any of the BP volunteers who wanted something more concrete than Beth’s word that they were working for legitimate purposes. “I’ll talk to my superior at GCHQ—Government Communications Headquarters,” Peggy expanded when Beth looked blank. “Where I work now. The name’s changed from the GC & CS days, but it’s the same stuff. Codebreaking when we’re not at war.”

“Is there any chance you could you get your hands on an Enigma machine through your office?” Mab broke in. “Surely they can’t all have been destroyed after the war.”

Peggy reversed for the telephone. “Let me ring a chap . . .”

It really was the most extraordinary thing, Mab thought. BP men and women came and went from Courns Wood—some of them Mad Hatters she had known like family, some vague acquaintances from night shifts or the canteen, every one vouched for. Peggy got them some mysterious authorizations, worked forty-eight hours round the clock, then departed looking elusive. The Prof came and went with an absent expression, two hours here, four hours there, whenever he could make the journey from Cambridge. A bespectacled fellow of Worcester College dropped in from Oxford and had a pencil in hand before “Asa, absolutely ripping—does everyone know Asa from Hut 6?” was fully out of Osla’s mouth. Harry’s cousin Maurice came, a cadaverous-looking man in the most expensive suit Mab had ever seen, then a fellow named Cohen with a Glasgow accent . . .

No one said Giles’s name. No one discussed his treachery. No one had to be warned to say nothing when they departed. “I’ve missed this,” Phyllida sighed when she finally had to leave.

Yes, Mab thought. I’ve missed it, too.

Though the work still had its stresses. “Beth,” Mab said, noticing her former billet-mate had snapped two pencils in the last half hour, “take five minutes. I’m going to trim your hair.”

“Why?” Beth blinked.

“Because you need a spot of tending if you’re going to get your focus back.” Cryptanalysts, Mab had learned, needed a certain amount of care if they were to perform at their peak. Thinking of Mrs. Knox and her wry indulgence of Dilly’s quirks—and the way she kept supplying her sudden influx of visitors with coffee—Mab shooed Beth into the washroom, borrowed a pair of scissors, and began smartening up that butchered blond hair while Beth slowly blinked her way back into the world around her.