Lowly Worm is the main protagonist of The Busy World of Richard Scarry and deuteragonist in its spin-off, Busytown Mysteries. He is Huckle's best friend and pet worm. He often stays with the Cats as a house guest. Although he attends school with the Cat children, Lowly can also be seen in more adult situations, like driving a street sweeper or working in the operating room of the Busytown Hospital.
- Keith Knight ([1993/1994]-2007)
- Paul Wensley (2007-)