The series takes place in Tracksville, a town located in a reality where human adults (with the exception of Santa Claus) have never existed and where kids run the stations and other locations and work together with the Mighty Express trains (who have the ability to talk and are intelligent) on epic adventures. The trains all have their own roles and duties within Tracksville, and their own individual set of tools and cargo cars to help them with their adventures so they always ensure to make their home a better place where trains and human kids alike live together in peace and harmony.