The main protagonists of the film are Fly, his little sister Stella, and their cousin Chuck. The three stumble across the laboratory of an eccentric marine biologist, Professor MacKrill, who has invented a "fish potion" that will turn humans into fish so they can survive after the polar ice caps melt and flood the Earth. He has also fortitiously come up with an antidote. Unattended, a thirsty Stella takes a drink of the fish potion, serving to escalate the film's plot. Not knowing it is his own sister, Fly throws the starfish he finds on the lab floor into the ocean. He then takes the potion himself in order to get her back, and Chuck takes it to avoid drowning when the boat he, Fly, and the Professor have taken to find Stella upsets in a storm.

The antidote, which has fallen into the ocean, is accidentally taken by a shark and its pilot fish, which embues them with human intelligence. Calling himself Joe, the pilot fish sparingly distributes the antidote to other fish, building up a civillization - and an army. The three children are scarcely reuinited when they become embroiled in Joe's scheme to take over the ocean...will they reclaim the antidote in time to avoid being stuck as fish forever?

Help! I'm a Fish (Hjælp, jeg er en fisk in Denmark) is an animated film made in the year 2000 and many people have not heard of it. It has been recently released in the US under the name A Fish Tale, more likely than not in an attempt to entice fans of A Shark Tale into watching it - an entirely unfair move if you ask me. Help! I'm a Fish is a unique film and I hope people who watch it do so while not trying to compare it to anything else.