When a yellow fusilier fish settles down in a cozy coral reef town, he introduces the town's sheltered residents, including a Mandarin dragonet fish who quickly becomes his friend, to the amazing places and creatures beyond the town's walls.
Splash takes his pals to go see his friend, LU, a fearless explorer in the deep. He has met Lu in his travels, and she has been an inspiration for Splash. Lu turns out to be a female football fish (the "Lu" stands for "bio-LU-minescent") who leads them on an adventure in the abyss. / Wave, the octopus, loves the musicality of Reeftown, but tries to keep others from discovering that he has no rhythm.