 |
James Mason as Mr. Grimes / Voice of Killer Shark |
 |
Bernard Cribbins as Mr. Masterman / Voice of Eel |
 |
Billie Whitelaw as Mrs. Doasyouwouldbedoneby / Old Crone / Mrs. Tripp / Woman in Black / Water Babies 'Gate Keeper' |
 |
Tommy Pender as Tom |
 |
Samantha Gates as Elly |
 |
Joan Greenwood as Lady Harriet |
 |
David Tomlinson as Sir John / Voice of Polar Bear |
 |
Jon Pertwee as Salmon |
 |
David Jason as (voice) |
 |
Una Stubbs as (voice) |
| Directing | Lionel Jeffries | Director |
| Writing | Charles Kingsley | Book |
| Writing | Michael Robson | Writer |
| Production | Peter Shaw | Producer |
| Camera | Edward Scaife | Director of Photography |
| Editing | Peter Weatherley | Editor |
| Visual Effects | Tony Cuthbert | Animation Director |
| Visual Effects | Jack Stokes | Animation Director |
| Visual Effects | Mirosław Kijowicz | Animation Director |
| Visual Effects | Leszek Galewicz | Animation Director |
| Visual Effects | Jan Baudouin de Courtenay | Animation |
| Visual Effects | Leszek Marek Gałysz | Animation |
| Visual Effects | Andrzej Kozłowski | Animation |
| Visual Effects | Elżbieta Morawska | Animation |
| Visual Effects | Jarosław Jakubiec | Animation |
| Visual Effects | Aleksander Piątkowski | Animation |
| Visual Effects | Cecylia Terlikiewicz | Animation |
| Visual Effects | Joanna Zacharzewska | Animation |
