A new, very different cast of friends has just arrived on the island of Sodor. Salty is a distinctive engine who loves the seashore, has a never-ending supply of stories, and can magically transform the normally troublesome trucks into happy, efficient workers. Harvey is an odd-looking fellow who quickly proves himself an indispensable addition to the railway, and Cyril the Fogman demonstrates that technology can never completely replace competent workers. Harold and Percy discover the true value of friendship and even Cranky benefits from a temporarily rosy perspective on the world. Finally, Thomas gets some help from an unexpected source--a dirty, grimy wreck that is somehow connected to Sir Topham Hat's past. Join Thomas and his friends as they discover that, while trains come in very different sizes and shapes, they share certain fundamental similarities that provide the basis of friendship.