Lots of twins have a special connection - being able to finish each other's sentences; sensing what the other is thinking; perhaps even knowing when the other is in trouble or in pain - but for 12-year-old twins, Matt and Emily Calder, the connection is beyond special. Together, the twins have extraordinary powers. They are able to bring art to life, or enter paintings at will. Their abilities are sought by villains trying to access the terrors of Hollow Earth - a place where all the demons, devils and creatures ever imagined lie trapped for eternity. The twins flee with their mother to the security of an island, off the west coast of Scotland, where their grandfather has certain protective powers of his own. But too much is at stake, and the twins aren't safe there either. The villains will stop at nothing to find Hollow Earth and harness the powers within...

In this thrilling sequel to Hollow Earth, Matt and Emily must stop someone from unleashing an army of mankind’s worst nightmares. In the Middle Ages, an old monk used his powers and a bone quill to ink a magical manuscript, The Book of Beasts. Over the centuries the Book, and the quill, were lost. Twins Matt and Emily Calder are Animare—just like their ancestor, the monk. The things they draw can be brought to life, sometimes with disastrous consequences. Now Matt and Em are being watched—hunted—because only they can use The Book of Beasts and the bone quill to release the terrible demons and monsters their ancestor illustrated. And someone is tracking down the lost Book of Beasts, page by page, and reassembling it. Matt and Emily have no choice: They must get to the bone quill first…before somebody gets to them.

THE LAST BATTLE FOR HOLLOW EARTH BEGINS... Lots of twins have a special connection - being able to finish each other's sentences; sensing what the other is thinking; perhaps even knowing when the other is in trouble or in pain - but for 12-year-old twins, Matt and Emily Calder, the connection is beyond special. They are Animare: they can bring art to life and enter paintings at will. But they are also Guardians, destined to safeguard the powers and existence of Animare everywhere. They are the first of their kind. Their childhoods have been spent in service to an ancient duty: preventing a breach in Hollow Earth - an alternate world that holds all the demons, devils and creatures ever imagined. But now their last battle for Hollow Earth begins...