Maria Tornlund

Major Palfrey is off to war. He warns his two daughters, Dinah and Dorinda, that while he is away they must behave themselves: "When there is wind on the moon, you must be very careful how you behave. Because if it is an ill wind and you behave badly, it will blow straight into your heart, and then you will behave badly for a long time to come." And so it proves: before long the girls are drinking a potion provided by the local witch and turning into kangaroos, getting stuck in the zoo, and staging an escape along with their new friends, a golden puma and a silver falcon.

Ratio Rasch, the president of planet Gyllenblå, has banned laughter and emotions in order to create a society based on reason. Police are constantly patrolling the planet and anyone caught laughing is imprisoned and given anti-laughter serum. Only a few members of an underground guerrilla oppose the president. On Earth, the eccentric Dr. Krull listens to signals from outer space and realizes that something needs to be done so he sends the two children Cecilie and Fredrik to Gyllenblå. Epicykel, a guerrilla member, senses their presence and hopes to get to them first but fails. The children are put in school, where Fredrik has great difficulty controlling his laughter but Cecilie adapts well. The guerrilla knows that laughter is contagious and Fredrik gives them new hope of returning laughter to the people of Gyllenblå.