Little Billy doesn't really believe his mother's stories about all the monsters living in the wood, so he is easily tempted to disobey her and go and see for himself. He doesn't find any Whangdoodles, Hornswoggles or vermicious Knigs, but the Gruncher who does chase him, billowing orange-red smoke, is even more terrifying. Billy finds this horrible Gruncher has been terrorising the other inhabitants of the wood for years- the Minpins, a tiny tree-dwelling people whose children are the size of matchsticks. But Little Billy doesn't want to spend the rest of his life up a tree, so he bravely offers to lead the Gruncher away and to his death, thus freeing the grateful Min Pins from his tyranny.