The coal mines under the hills of Dover were dark and confined, but they were alive. They hummed with the vibration of pickaxes striking stone, rumbled with carts full of coal pulled by ponies over metal rails, and echoed with men’s voices, as deep and gravelly as the earth they dug, shouting out orders, singing Irish tunes off-key, and laughing over jokes Thomas would never dare repeat at home.

The tunnels beneath the Western Front lay deadly quiet. Their silence crept across Thomas’s skin in gooseflesh he feared no amount of heat could drive away, and for the first time in two weeks, he wished George would start talking again.

But no one spoke. Not after Bagger’s warning.

As they followed the man farther beneath the battlefield separating the Allied trenches from the Germans’, approximately a city block away, shadows, cast by candles and electric lanterns burrowed into the narrow clay walls, twitched and scattered down the tunnel like angry apparitions. Timber beams, set three hand widths apart and etched with pencil markings, braced the tunnel walls. Thomas recognized some letters, but he couldn’t decipher what they were or what they meant. He had always struggled with reading and writing, and his inability to decipher letters as easily as his classmates had resulted in daily punishments from his teacher. Miss Barry wore a metal thimble on her right pointer finger, which she tapped against Thomas’s head every time he mispronounced a word. Thomas went home every day humiliated and with a terrible headache. After five years of such cruel punishment, Miss Barry deemed Thomas unteachable, and Mr. Sullivan pulled his youngest son from school to work with him and James in the coal mine.

Twice, Bagger led them down ladders inside large metal tubes, past pulley systems, deeper into the earth, until they reached the lowest gallery, set one hundred feet below the battlefield. They then began the long walk up a gentle incline in the direction of Messines Ridge. Along the way, they occasionally passed men hauling full sandbags on small rubber-tired trams to the shafts to be transported to the upper galleries. Thomas assumed the bags’ final destination was the side room just inside the tunnel entrance. Remembering the sandbags’ purpose, his steps faltered at the thought of an enemy breach of the trenches and being walled inside the tunnels with no escape. With a shudder, he pushed the horrific thought from his mind and hurried to catch up with the others.

As they made their way farther beneath no-man’s-land, Thomas found himself grateful for his lack of height, for the first time in his life. He didn’t have to bow his head or hunch his back like Bagger or the other boys. George hit his head more than once on the timber beams but didn’t complain. They all followed Bagger in silence, even Frederick.

Thomas lost count of the side tunnels that sprouted out from the main gallery. He wasn’t sure where they led or what the clay kickers were digging for, but it was obvious that like ants, they were creating a maze of tunnels beneath no-man’s-land.