James Henry Trotter
Aunt Sponge / Glowworm (voice)
Aunt Spiker
The Magic Man
Grasshopper (voice)
Centipede (voice)
Ladybug (voice)
Miss Spider (voice)
Earthworm (voice)
James' Father
James' Mother
Girl with Telescope
Woman in Bathrobe
Cop
Reporter #1
Reporter #2
Reporter #3
Street Kid
Hard Hat Man
Centipede (singing voice) (uncredited)
Glowworm (singing voice) (uncredited)