Thomas and Diesel are to load and shunt trucks of stone for Henry, but they get sidetracked when Diesel claims he is faster than Thomas - and declares a backwards race to prove it. Unfortunately, the three heats (which end in a draw) cause Mavis, 'Arry and Bert to be derailed after Thomas and Diesel collide with them. When Henry arrives, none of the trucks have been loaded. While Thomas arranges the train and collects Rocky to put Mavis, Arry and Bert back on the rails, Diesel clears away the mess from the races. When the two are done, Diesel challenges Thomas to another race, which Thomas orders to be forward. This time, both arrive at the quarry gates at the same time.