Six animated adventures following tank engine Thomas and his locomotive friends. This instalment sees both volcanoes and dinosaurs on Sodor Island while Thomas and the other engines go about their work. The episodes are: 'Marion and the Dinosaurs', 'Millie and the Volcano', 'Timothy and the Rainbow Truck', 'Samson at Your Service', 'Emily Saves the World' and 'Samson Sent for Scrap'.