Pisces, or Pi, is a young orange wrasse living with his parents, Pike and Piper, in the polluted harbor of Boston until a fishing boat scoops them from the sea.

Meg and Percy take Pi to live with his aunt Pearl on an exotic Caribbean reef.

Upon arrival, Pi comes across three elderly marlin named Moe, Jack, and Manny, who direct him toward Pearl's home.

On his way there, Pi immediately falls in love with Cordelia, a beautiful angelfish who has appeared on the cover of National Geographic.

However, Pi soon encounters Troy, a tiger shark, who not only terrorizes everyone in the reef community but also has his eye set on Cordelia to become his mate.

She is a fortune-teller, along with her assistant Madge, a starfish, and uses a pink pearl Dylan's late father gave her as a crystal ball.

Pearl reads Pi's future and sees that he is destined for great things and will find his destiny on the reef.

Pearl then tells Pi he can go anywhere, excluding an abandoned shipwreck and a forbidden place called "Flat Bottom."

Dylan tells Pi about Nerissa, a wise old turtle who lives in the abandoned shipwreck and practices martial arts, leading to rumors that he is a wizard.

Eventually, they stumble upon Flat Bottom, the open sea outside the wildlife sanctuary, free for humans to come with their fishing nets.

Dylan leaves after a close encounter, and Pi sees Cordelia, but initially, they do not interact until she screams after getting a lure stuck in her fin and comes to her aid.

At the amphitheatre that night with Cordelia, Pi learns about the performer Thornton, a seal who fought an enormous beast.

Nerissa leads Pi down a valley with obstacles including razor-sharp elkhorn coral, burning fire coral in a dark enclosed tunnel called Bottleneck Alley, and finally, the West Indies current full of dangerous Portuguese man o' war.

Nerissa reveals the story of his blue pearl to Pi, and he gives it to his wife, but she gets hooked in the open sea and taken away.

[4] eFilmCritic.com's David Cornelius described it as "undoubtedly one of the cheapest, ugliest cartoon features ever produced", criticizing its CGI, graphics, and animation.

[6] Tracy Moore of Common Sense Media gave the film two stars out of five, saying that it was "an animated ocean tale has lots of scuffles and bullying.