The story of "The Three Billy Goats Gruff" has been Norway s best-loved folk tale for nearly 200 years, and this lively retelling features exceptional illustrations by the talented Gaye Chapman The Billy Goats Gruff are headed up the mountain, but to get there they must first cross a bridge. The trouble is, a troll lives underneath it and he is very keen to gobble up those goats, one after the other. Luckily, the Billy goats are smart. Luckier still, the troll is stupid.