Skid, the littlest tractor in the equipment yard, wants to be mighty like the giant bulldozers, tall cranes, and massive diggers who tower over him. But all the big machines tell him he is just a dinky tractor with a putt-putt engine. When a new tunnel caves in only a small opening is left at the entrance and the only one who can fit through the opening is Skid – who is afraid of the dark. Now it’s up to the tiniest tractor to save the day. Can Skid find the courage to do what he was made to do and prove that he doesn’t have to be big to be mighty?