S05E01 - The Mole Machine
Synopsis
Mr. Fixit is delighted with his new invention––a machine that will take him to the center of the Earth, and it's all ready for a solo trip. Except the solo trip ends up being not so solo when Huckle, Lowly, and Mr. Frumble end up tunneling under Busytown. Up on the surface, Busytown is dealing with some serious traffic but now, thanks to the Mole Machine, Busytown's all set for its first ever subway.