While staying at a hotel in England with his grandmother, Helga, a young boy named Luke inadvertently spies on a convention of witches. The Grand High Witch reveals a plan to turn all children into mice via a magical formula. When they discover the eavesdropper, the witches test the formula on him. Now, with the help of Helga and hotel manager Mr Stringer, Luke the mouse must fight back against the witches.
| Actor | Role |
|---|---|
 Jasen FisherLuke Eveshim | Luke Eveshim |
 Mai ZetterlingHelga Eveshim | Helga Eveshim |
 Anjelica HustonMiss Eva Ernst | Miss Eva Ernst |
 Charlie PotterBruno Jenkins | Bruno Jenkins |
 Rowan AtkinsonMr Stringer | Mr Stringer |
 Bill PatersonMr Jenkins | Mr Jenkins |
 Brenda BlethynMrs Jenkins | Mrs Jenkins |
 Jane HorrocksMiss Irvine | Miss Irvine |
 Nora ConnollyBeatrice | Beatrice |
 Rose EnglishDora | Dora |
 Jenny RunacreElsie | Elsie |
 Angelique RockasHenrietta | Henrietta |
 Rosamund GreenwoodJanice | Janice |
 Sukie SmithMarlene | Marlene |
 Emma RelphMillie | Millie |
 Annabel BrooksNicola | Nicola |
 Vincent MarzelloLuke's Father | Luke's Father |
| DDarcy FlynnLuke's Mother | Luke's Mother |
 Ola OtnesErica's Father | Erica's Father |
| MMerete ArmandErica's Mother | Erica's Mother |
| EElsie EideErica | Erica |
 Jim CarterHead Chef | Head Chef |
 Roberta TaylorWitch Chef | Witch Chef |
| AAnne TirardLady #1 | Lady #1 |
| LLeila HoffmanLady #2 | Lady #2 |
| JJohan Sverre MyhrePoliceman | Policeman |
 Arvid OnesPoliceman | Policeman |
 Sverre RøssummoenPoliceman | Policeman |
| GGrete NordråNorwegian Witch | Norwegian Witch |
| SSerena HarraginDoctor | Doctor |