At the beginning of this episode, the Sprites and Color Kids are preparing for a Flower Festival parade. The Sprites are decorating everything with flowers and the Color Kids are practicing their instruments. Shy Violet has invented a high powered telescope so that they can see where color is needed all over the universe and is showing it to Rainbow. Rainbow sees something strange flash across the sky, but by the time she looks again, it's gone.
Starlite and Skydancer are also getting ready for the parade. The only thing missing is a grand marshall, so Starlite suggests that they go to Earth and get Brian. Rainbow and the Color Kids love the idea, so Rainbow and Starlite take off to Earth to pick him up.
In The Pits, Murky and Lurky were spying on Rainbow Land as they tuned up a spaceship Murky had built. In the sky above them, another spaceship was flying - piloted by Sorell the Sorcerer. He'd gotten lost on the way to his Mechanical Spells Convention and then his ship had malfunctioned. He was forced to crash land in The Pits just as Murky was wishing for a way to destroy the Color Caves.
Lurky figures that Sorell's arrival meant he was there to grant Murky's wish and Sorell takes advantage of this misunderstanding. He tells Murky he will grant any one wish as long as Murky will fix his spaceship. At first Murky does not believe in Sorell's powers, but when Sorell turns him into a duck temporarily, he changes his mind and wishes for Sorell to destroy Rainbow Land's Color Caves.
They head back to Murky's laboratory to discuss how to destroy the Color Caves. Sorell gets the idea to create a comet from an evil rainbow to fall down and crush the Color Cave. But he warns that at the heart of every evil rainbow is a good rainbow, and if a good rainbow makes contact with the bad, the good rainbow will always win.
Sorell conjures a book out of thin air to get the ingredients to make a comet. He needs a cup of water from Rainbow River, a Color Crystal from the Color Cave, and a patch of fur from a Sprite. Murky complains that he'll have to go to Rainbow Land to get those things, but Sorell reminds him that if he does not, the Color Caves will never be destroyed. So Sorell disguises the Grunge Buggy as a float for the parade and Murky and Lurky take off to Rainbow Land.
First they head to Rainbow Falls to get some water out of the Rainbow River. Then, they drive into the Color Caves to grab a Color Crystal. The Sprites in the Cave were too fast for them, so they had to drive down to Rainbow Land to get a patch of Sprite fur, then they ran back to The Pits.
Once they arrive, Sorell tells them how to make the evil rainbow. They pour the water from the Rainbow River into a bowl, add the Sprite fur, then add the Color Crystal. An evil rainbow shoots out from The Pits into space, and a comet comes back in its place. Sorell says that the comet will hit the Color Saves at high noon. Murky and Lurky are so thrilled that they start dancing around. This annoys Sorell, so he turns Lurky into a frog. Murky asks that he be turned back so that they can go find the parts for his spaceship, so he does so.
Back in Rainbow Land, Puppy Brite and Kitty Brite are watching through Shy Violet's telescope. Kitty Brite sees the comet, then so does Puppy Brite. They run to get the Color Kids and the Kids see what's coming. They immediately rush to the Rainbow Alarm to call Rainbow Brite back to Rainbow Land.
Meanwhile, Lurky decided to strip the parts for Sorell's ship from Murky's ship. They fixed Sorell's ship right up and he took off. At the same time, Rainbow and Starlite were almost back to Rainbow Land with Brian when they saw the Rainbow Alarm. They hurried even faster to find out what the problem was. Shy Violet was already busy calculating when the comet was going to hit, and realized they only had a few minutes to spare.
As Rainbow makes her way back, Lurky realizes that the comet is too big and won't just destroy the Color Caves - it will destroy the entire planet! Murky, no longer having a spaceship to escape in, decides to go to Rainbow Land and steal Rainbow's color belt in an attempt to destroy the comet himself. Rainbow has also returned by this time and discovered the severity of the problem.
While Rainbow Brite tried to figure out what to do, Murky arrived in Rainbow Land. He and Lurky snuck up behind her in the Grunge Buggy and stole her belt. Rainbow chased after them, and the buggy stopped when Lurky accidentally hit the petal too hard. Rainbow demanded the belt back and Murky gave it to her. Lurky wondered what to do next, since only a good rainbow could destroy the comet. Rainbow immediately got to work on shooting a rainbow directly at the comet.
The rainbow penetrated the comet and caused it to explode before hitting the ground. Rainbow Land was saved!
The Flower Festival parade was able to go on as expected, and the Color Kids had an extra pair of helpers to throw out flowers - Murky and Lurky! It was the worst punishment Murky had ever endured.
In the beginning of this Episode, Canary Yellow is seen playing a flute and Patty O'Green is seen playing a oboe. At the end of the episode, their instruments are switched. We'll just assume that the girls can play both and decided to trade ;)