Geoffrey Cranbrook, a stuffy retired Judge, is unexpectedly asked to look after Henry, his 10-year-old nephew. Geoffrey is trying to write an exceptional book and not wanting to be disturbed, asks the boy to remain in his bedroom. Henry however, is incapable of sitting still and learning that his Uncle is suffering from 'writer's block', slips into a fantastical world to try and find a cure. There he meets Raygo Rattlegum, an elf-like hunter who reveals that to restore someone's imagination you need a single drop of blood from a Voydarkatron - a hideous beast that sucks people's brains out of their eye sockets.