Les Pyjamasques et Utupë, l'esprit de la forêt (English:
The Pajamasks and Utupë, the spirit of the forest) is the fifth book of Les Pyjamasques which was published by Éditions Gallimard on September 25, 2008.
In the shape of a statuette, Utupë, the spirit of the forest, escapes from the museum! He wants to return to his forest with millennia trees, on the other side of the Earth. But how to go? He gets lost in the streets of Tarabiscoville. Fortunately, Les Pyjamasques will guide him.
Despite the book series being aimed at children, this book contains references to violence and death such as Agent Pin and Agent Pon threatening to shoot the Original Les Pyjamasques "without warning", and the Original Les Pyjamasques thinking that Utupë is presumably dead after escaping a truck that was attempting to crush them. This book is even banned because it's too inappropriate for children.
It is revealed that the book breaks the fourth wall as there is one page of the book showing Agent Pin and Agent Pon near a library building containing books of "Les Pyjamasques au zoo" and "Les Pyjamasques et Lilifée" that are seen in an obscure view.