Happy was sent to the past through the power of the Three Sacred Treasures! There, in Sciencity, he meets Marice, a human girl shut away in a tower. She's been using her magic, Evolution, to make "Marice Friends": animals that can walk and talk like human beings. But General Star has been performing cruel experiments on the Marice Friends and using them as living weapons! Happy joins forces with Marice's guardians, the Three Beast Musketeers, along with Foxy and a young Tortoise, to try and break Marice out and save the animals. Will they succeed...?!