Abbey of Ruac, rural France: A medieval script is discovered hidden behind an antique bookcase. Intrigued, Hugo enlists the help of archaeologist Luc Simard and the two men go exploring. When they discover a vast network of prehistoric caves, buried deep within the cliffs, they realise that they've ...

Abbey of Ruac, rural France: A medieval script is discovered hidden behind an antique bookcase. Intrigued, Hugo enlists the help of archaeologist Luc Simard and the two men go exploring. When they discover a vast network of prehistoric caves, buried deep within the cliffs, they realise that they've stumbled across something extraordinary.