The Adventure Series: Mountain of Adventure (Book 5)

In the fifth thrilling chapter of the series, a peaceful hiking holiday in the Welsh mountains becomes a journey into the heart of a terrifying secret.

What begins as a simple trekking expedition for Philip, Jack, Dinah, and Lucy-Ann soon takes a sinister turn. While exploring the rugged peaks and deep vales, the children are drawn to a mysterious, fog-shrouded mountain that the locals speak of only in hushed tones. Their curiosity leads them to a discovery that defies explanation: the mountain is hollow, and someone—or something—is living inside.

As they venture deeper into the mountain's core, the group uncovers a high-tech secret base run by a brilliant but dangerous scientist with a plan for world domination. Trapped within a labyrinth of metal and stone, the children must use every ounce of their ingenuity to escape. With Kiki the parrot providing vital distractions, the team must navigate gravity-defying experiments and outwit a private army to stop a catastrophe and find their way back to the surface.