Peter JacksonRéalisateur Donna AkerstenSamantha the Cat / The Sheep (voice) Stuart DevenieSebastian / Dr. Quack / Daisy the Cow / Sandy the Chicken (voice) Mark HadlowHeidi / Robert / Barry the Bulldog (voice) Brian SergentWynyard the Frog / Trevor the Rat / The Fly (voice) Ross JollyHarry / Dennis / Abi Bargwan / Mr. Big / Pekingese / others (voice) (uncredited) Peter Vere-JonesBletch / Arfur the Worm (voice) Mark WrightSid the Elephant / The Cockroach / Louie the Fish (voice) Danny MulheronHeidi the Hippo (uncredited) Jay SnowfieldKiller man (uncredited) Doug WrenBletch (voice) (uncredited) Peter JacksonAudience Member in the Theater (uncredited) Fane FlawsMusician Frog (voice, uncredited)