The Tunny machine sat directly in front of Sophie on a long counter. It was squat and square in shape, perhaps a bit bigger than a wooden milk crate. Or at least she was assuming that it was a Tunny machine, never having seen one before. However, Sophie had seen many teleprinters at Bletchley, all similar to the teleprinter that was attached to this machine. Rolls of paper ribbon were stacked up next to it on the counter, used, perforated fragments curling out of a metal bin underneath.

Sophie went directly to the boxy machine and discovered that the box itself was simply that—a metal cover placed over the machine that sat beneath, presumably to protect it from dust and debris. She lifted it carefully and was rewarded by a maze of small electronic parts and pieces, all sitting above a neat row of twelve rotors that looked like sprockets from a bicycle. Sophie took a half step back and raised the little camera. With some shock, she realized that her hands were shaking. After everything that had happened, after everything that had brought her here, this close to achieving her mission, her nerves chose this moment to make themselves known?

A bubble of hysterical laughter rose in the back of her throat, and she swallowed it lest she make a sound. This was absurd, she reflected, but reassured herself that it was only a natural reaction. And on the heels of that thought, another gurgle of manic laughter threatened, because if ever there was a time for Sophie to embrace the unnatural accusations hurled at her since she was eight, now would be it. She took three deep breaths through her nose and out her mouth, focused on the mountain of sprockets and wires and gauges responsible for messages that wreaked death across a continent, and began taking photos.

The steady clicking as she opened and closed the camera to advance the film was the only sound in the tomblike space. She took photos as quickly as she could from as many angles as she could without risking blurring the image. When she was satisfied that she had captured as much as possible, she replaced the machine’s cover and turned her attention to the cabinets that sat exactly as Estelle had described.

She set the little camera down and pulled out her set of lock picks. It took her less than a minute to open the cabinet, the simple lock giving way easily. She pulled the upper of the two drawers open, and her stomach sank. It was empty. She crouched in front of the lower drawer and opened it. This one was not empty, and instead, contained a neatly organized stack of what looked like about a half-dozen thin manuals.