The vibration grew into a low rumble, and with a groan of ancient mortar, a section of the stone wall recessed and slid sideways.

“A secret passage!” Emma exclaimed, her fear momentarily replaced by the thrill of discovery.

“Look!” Aiden pointed his stick. Beyond the wall lay a narrow tunnel, the air smelling of damp earth and old coal.

“We can’t stay here,” Michael said, shaking the flashlight until it gave a weak, flickering yellow glow. “The man in the trench coat is probably right outside that door. This tunnel is our only way out.”

Olivia held Aiden’s hand tightly as they stepped into the narrow passage. The walls were reinforced with rotting timber beams. “This must have been part of the Underground Railroad, or maybe an old smuggling route,” she whispered.

As they moved deeper, the tunnel began to slope upward. Suddenly, Emma tripped over something hard. Michael swung the light down. It wasn’t a rock—it was a heavy, rusted iron key sitting on a ledge.

“That looks like it fits the lock on the wooden box!” Emma said, her eyes widening.

Just as Michael reached for the key, a faint scratching sound came from behind them. It wasn’t a person—it sounded like claws against stone.

“Run!” Olivia hissed.

They scrambled up the incline, their breath coming in short gasps. The tunnel ended at a wooden trapdoor overhead. Michael shoved against it with all his might and Olivia pushed her weight against also. It creaked, resisted, and then flew open with a shower of dust.

The children scrambled out and found themselves in a place they knew well: the old potting shed at the very edge of the wooded yard. But their relief was short-lived. Through the shed’s grimy window, they saw a black sedan idling at the end of the driveway—a car they had never seen before.

“He’s not alone,” Michael whispered, watching a second man in a dark uniform get out of the car. “And they’re heading straight for the front door!”

Read more at Hartman Mysteries