Paul Terry

James Henry Trotter

Miriam Margolyes

Aunt Sponge / Glowworm (voice)

Joanna Lumley

Aunt Spiker

Pete Postlethwaite

The Magic Man

Simon Callow

Grasshopper (voice)

Richard Dreyfuss

Centipede (voice)

Jane Leeves

Ladybug (voice)

Susan Sarandon

Miss Spider (voice)

David Thewlis

Earthworm (voice)

Steven Culp

James' Father

Susan Turner-Cray

James' Mother

Cirocco Dunlap

Girl with Telescope

Kathryn Howell

Woman in Bathrobe

Mike Starr

Cop

Michael Girardin

Reporter #1