Doc and Yoyo join Casper, an upstanding honest blonde commoner. He fulfills a double prophecy about marrying a wicked king's daughter. Casper first refuses her hand because he lost his heart on the way to the palace, until she appears: it's the same. The king poses a hard condition: bringing three golden hairs from the devil's head. Travelling to Hell, the trio promises to answer three personal questions. In hell, they find the devil to be domineered by his haughty grandma. They get her to bet for the hairs against their lives whether she can solve three riddles. Thus they fulfill all four their promises. The gold they earn from the grateful commoners brings Casper a surprising bonus.
—KGF Vissers