Génibus, an ambitious inventor with dreams of glory, decides to create an ultramodern sleigh for Santa Claus: without reindeer, eco-friendly, high-tech, designer and ultra-comfortable. Santa Claus, too attached to his reindeer with whom he has been distributing presents since the dawn of time, is not convinced by the machine. Ready to do anything to get Santa to use his Galactic One sleigh and finally have his moment of glory, Genibus will find the devious witch Doramoche to try to make the reindeer disappear in a very surprising way... Will his call for help to children around the world allow Santa to find his reindeer friends with such different characters?

Santa Claus is very annoyed: the witch Doramoche has stolen the key to his trunk where he preciously keeps his magic sack. Without this sack, it is impossible to distribute presents to children all over the world! Santa, Detective Saitout, Genibus and the elves will have to be very clever to solve the enigma of Doramoche's grimoire and find the hiding place of the key.