Oliver and his best friend Troll run a cafe in the woods. They make the best cakes - their troll customers would much rather eat cakes than children! One particularly busy day in the cafe, Oliver's sister Dolly disappears, so Oliver and Troll set off to find her. Their search takes them up Munch Mountain, where the biggest, meanest and grumpiest troll in the world lives. Oliver doesn't believe all the scary rumours, but Troll's not so sure.