Jeanne is hospitalized for appendicitis when an ogre suddenly appears and steals her heart. But dying is out of the question! A musketeer and his talking cat appear at the right moment and lend her a dragon’s heart, but it will only work for a day.

In short, the young girl, accompanied by these strange companions, has only several hours to find her vital organ. A frantic high-speed chase through Paris begins, during which Jeanne will have to be courageous and resourceful. She will head through a market with goblins, fly on a hotair balloon, meet a ghost friend, and attend an epic battle between the gargoyles and the statues of Notre-Dame Cathedral, which have come to life...

And when she finds the person responsible for the appearance of the ogre, she will have to fight with the magic she has discovered in herself, and that could change everything.