Eleven-year-old Darwen Arkwright's ordinary life changed forever when he was given a magical mirror, a portal to the wonderful world of Silbrica. Darwen defeated the terrible monsters released from the mirror once. Now, an even more terrifying beast has escaped through the mirror. Darwen and his friends, Rik and Alexandra, must journey to Costa Rica to save the world from a giant tentacled creature that leaves destruction in its wake. This time, old allies can't be trusted, and the danger runs deeper than Darwen could have ever imagined.

The problem with doors is that they open both ways. There are monsters inside, and some of them are trying to get out ...