What did Professor Childermass's eccentric brother mean by the
mysterious riddle he attached to his will? And why does he insist the
professor spend the summer on his deserted estate in order to earn his
inheritance? The professor, Johnny Dixon, and Johnny's friend Fergie
are determined to find out. But when they journey to the ramshackle
mansion, they make a horrifying discovery. Unless they unravel the
baffling mystery fast, an evil madman will succed in unleashing a force
so powerful it could destroy the entire world!