On the first day of spring, Zak and his dog Ziggy are waiting at the river to meet Ivy for a day of fishing when a tree branch falls and hits Zak on the head. When he comes to, Ivy has arrived, and shows him a bottle her grandmother has given her. She tells him it contains magic bubbles.
The two children begin blowing bubbles, and a giant bubble appears, carrying an unusual creature inside. He introduces himself as Professor Aquius Botanicus Angelicus of the planet Quantia, on a search for pure water to fuel the bubble he uses as a spaceship.
Professor Angelicus is trying to get home to Quantia in time for the planet’s Rainbow Festival, held once every billion years. The water in the river isn’t pure enough to fuel his ship for such a long journey, and he asks Zak and Ivy for their help. An easy task proves difficult, and the three friends, along with Ziggy, find themselves traveling all over the world, from the bottom of the ocean to the rainforest looking for pure water. Along the way, they are hindered by ever more apparent problems in earth’s environment and by the creature, Borrell - the evil, shape-changing embodiment of negative energy and bad thoughts.
With help from animal friends, they eventually reach the Polar Ice Cap, where they defeat Borrell and find the water to fuel Professor Angelicus’ bubble ship. In gratitude, the Professor takes Zak, Ivy, and Ziggy with him to the Rainbow Festival, where they receive special thanks from the Quantian Grand Council, and magic tools – a wand, a pipe, and a collar for Ziggy – that will allow them to travel in the sparkle.
Zak comes to on the riverbank, wondering if it was all a dream, when he spots Ziggy wearing his magic collar…