Engine driver Jeremiah is passionate about trains and the railway company he works for. Fortunately, his two grandchildren Thomas and Sarah share their granddad's passion for trains and railways. But the wealthy new owner of the railway company considers Jeremiah too old and hastily fires him devastating Jeremiah and his grandchildren. The railway owners irritating 9 year old son Justin soon realizes that young Thomas has been taught to drive a locomotive by his granddad. Thomas, Justin and three of his friends find an old locomotive in the yard and decide to give it a test run. Soon the kids are stuck on board a runaway train. Can Jeremiah and the railway owner settle their differences and rescue the kids from the impending disaster?