In the shadows of Walton Hall a demon lurks. His name: Mephistopheles. In 1586, young John Striven struck a bargain with him in return for help against his murderous foster brother. Nice work for a demon - or it should have been. Because somehow, his plan to trap the 12-year-old went wrong. All he needs now is another soul, in similar desperation, to call on him. Enter 13 year-old Henry Fowst. A pupil at Northwell School, Henry longs to win the Northwell History Essay Prize. Exploring the school's sixteenth century library, he stumbles across the diary of a boy his own age beginning this 20th day of Januarie, 1586... Soon Henry is absorbed in John Striven s struggles with his jealous foster-brother, Thomas Walton, who, it seems, will stop at nothing to be rid of him. Then matters take a darker turn. Battling to escape his own enemy, Henry finds his life beginning to imitate John s and when the diary shows John summoning an Angellick Spirit to his aid, Henry eagerly tries the same. Unfortunately, calling up Mephistopheles lands both boys in greater danger than they d ever bargained for...