- Johan Kaart - Wim Verstappen (φωνή)
- Cor Witschge - Joris (φωνή)
- Jenny Arean - Miss Jones' Cat / Kater's Mother (φωνή)
- Lex Schoorel - Λοχίας (φωνή)
- Rieneke Debree - Kitty (φωνή)
- Hetty Heyting - Plopje / Miss Jones' Dog (φωνή)
- Huib Broos - Kater / Καθηγητής / Ντετέκτιβ / Miss Jones' Horse (φωνή)
- Trudy Labij - Annabell (φωνή)
- Willy Brill - Miss Mabel Jones (φωνή)