In a magical undersea world where dragons rule and humans are feared, a naive young dragon forms an uneasy alliance with the sea's greatest enemy - a human girl.

Louis, a retired man, resists the overprotection of his daughter Nina to keep his independence.

In a castle full of hedgehogs, an engineer is trying to satisfy her king, who wants her to create an unusual machine. After being thrown away for her failure, she finds an hedgehog on her head which gives a brilliant idea. She presents her new invention to the king, astonished : she reveals a pinscreen made out of hedgehogs and their spines.