By day, Connor, Greg, and Amaya head to the library to celebrate Greg's birthday. But when they arrive, all of the party suppllies including the lizard cake was stolen. By night, it was Night Ninja and his Ninjalinos who has the party supplies to plan his own birthday party. The PJ Masks tries to get the lizard cake back, but the only thing that gets in the way of completing their mission was Catboy's love for the cake and decorations that are based on Master Fang.