Cale is disturbed by premonitions of a great disaster. The waters are rising, and the Ancient Enemy watches their every move. Cale, Rosie and Peter must learn about their powers before time runs out. They draw Uncle Andrew into the search as they unravel the connection between the two worlds. They are joined by a confused gardener and stalked by a mysterious young man. The Great One waits patiently to be found. At the Great College Master Gerard and young Piet seek for answers in the ancient, hidden archives. All hands will be needed if the worlds are to be saved.