It's Christmas in a small village in the Pyrenees. Olentzero is a beloved character who represents the Christmas spirit and distributes gifts to children. He has already received all the letters from the children in the valley and is watching their behavior through the "magic log" burning in his fireplace. An evil businessman has arrived in the village and wants to cut down the forest to build a ski resort. He steals Olentzero's "magic log" and all the letters, putting the children's gifts in jeopardy. Anjé, a young charcoal burner, is tasked with setting things right. With the help of the other children in the village, they will go through endless adventures and dangers until normality returns to the valley and Christmas can continue as usual.

In the year 1512, two insects embark on an expedition that becomes the adventure of their lives.