In a magical world, cities are built with children's smiles.

But something strange is happening... the smiles are disappearing!

Leo and Mia, curious friends, set out to solve the mystery.

They follow clues and meet sad children with no smiles.

Leo and Mia discover a factory stealing the smiles.

They devise a plan to stop the factory and save the smiles.

They gather all the children and lead a joyous revolt.

With their clever ideas, Leo and Mia succeed.

The city becomes colorful again, filled with laughter and smiles.

Leo and Mia are hailed as heroes of happiness.