Mike and his trusty steam shovel, Mary Anne, dig deep canals for boats to travel through, cut mountain passes for trains, and hollow out cellars for city skyscrapers -- the very symbol of industrial America. But with progress come new machines, and soon the inseparable duo are out of work. Mike believes that Mary Anne can dig as much in a day as one hundred men can dig in a week, and the two have one last chance to prove it and save Mary Anne from the scrap heap. What happens next in the small town of Popperville is a testament to their friendship, and to old-fashioned hard work and ingenuity.