Bamse, Lille Skutt and Skalman embark on an adventure that takes them through the Troll Forest to the City of Thieves to save Grandma from the villainous fox Reinard.

Bamse’s friends go on a quest to find the Thunderbell, the ingredient that makes Bamse strong. Meanwhile, the sly Reinard pretends to be a good guy to supplant Bamse as…