Dunderklumpen lives all alone in the mountains of Jämtland. One Midsummer's Eve when he feels very lonely he sets off on a journey to find friends.
| Actor | Role |
|---|---|
 Beppe WolgersBeppe | Beppe |
| JJens WolgersJens | Jens |
 Halvar BjörkDunderklumpen / Jorm (voice) | Dunderklumpen / Jorm (voice) |
 Håkan SernerLionel (voice) | Lionel (voice) |
 Gösta EkmanDummy (voice) | Dummy (voice) |
 Toots ThielemansPellegnillot (voice) | Pellegnillot (voice) |
| LLotten StrömstedtDoll (voice) | Doll (voice) |
 Sif RuudElvira Fattigan (voice) | Elvira Fattigan (voice) |
 Birgitta AnderssonBlomhåret (voice) | Blomhåret (voice) |
 Stig GrybeOne Eye (voice) | One Eye (voice) |
 Hans AlfredsonBee (voice) | Bee (voice) |
| KKerstin DunérSelf | Self |
 Bert-Åke VargOld House (voice) | Old House (voice) |
| CCamilla WolgersCamilla | Camilla |