“Your objective is to put yourselves into a position where you can confirm the existence of the cipher device at the Ritz Hotel,” Buckmaster said. “Once that is confirmed, you are to study the machine, photograph it at best, sketch it at worst. But, most importantly, you are to copy whatever tables or codebooks accompany it that detail the settings of the device. If the device settings of the ciphered message are known, I am told we have a hope of decoding it quickly enough to make a difference.”

“I’d prefer to steal the books,” Gerard said. “It would be faster. Copying sounds time consuming. Risky.”

“We do not want the Germans to know what we know,” Sophie said quietly. “Or they will change the rules again.”

“I beg your pardon?” Gerard was frowning at her. “What’s that supposed to mean?”

“It means that Madame Beaufort is correct,” Buckmaster said. “No matter what happens, your efforts cannot be discovered. You cannot be discovered. If it comes to it, destroy whatever evidence you’ve collected. We cannot afford to start over should the Germans fear we’ve penetrated their ciphers. Not now.”

Gerard crossed his arms.

“You will be provided with everything you need at the time of the drop. Weapons conducive to concealment—blades and the like, whatever you favour—though you will not carry firearms when you travel,” Miss Atkins continued. “The Nazis are very suspicious of anyone who is armed, and we do not want to give them a reason to look too closely. Tempo’s purported injury and age should prevent him from being an obvious target of roundups for German factories. There is paperwork and a supporting address in place in Marseille should the credentials of Enchanté Cosmetics be scrutinized. Your French identification papers are in order, and you’ll have train passes and ration books. You should get through inspections but, of course, we can offer no guarantees. I cannot stress enough that what you will be doing is extremely dangerous.”

Gerard uncrossed his arms and glanced at Sophie, still frowning fiercely.

She gazed back, wondering if the man was as disgruntled as he appeared or if his expression was merely one of concentration as he considered the details of the mission. It was difficult to tell.

“When do we leave?” Gerard demanded.

Buckmaster cleared his throat. “With luck, a fortnight. A bus will take you to Tempsford today. Major James Reed will be waiting for you there. We need a full moon and favourable weather conditions—let’s hope we get them and hope that ground conditions remain the same. The countryside is too often crawling with Gestapo and police. You should also be aware that the pilot may be required to abort the drop if the reception committee fears they’ve been compromised in any way.”