Time Out says
Danish directors Hegner and Fjeldmark wanted 'to create an animated film based on an ordinary daily situation'; and this, believe it or not, is it. Thirteen-year-old Fly takes kid sister Stella and dweeby cousin Chuck on a fishing trip. Stranded by the tides, they stumble on an underground laboratory where dotty Professor Mac Krill has devised a potion to turn humans into fish (in anticipation of the polar ice caps melting and humans being forced to survive underwater). After Stella accidentally drinks some of the potion and turns into a starfish, the boys have to take it, too, to find her - but if she doesn't get the antidote within 48 hours, she'll remain a fish forever. This underwater adventure, complete with Busby Berkeley-style synchronised swimming sequences, is further complicated by the antidote falling into the fins of megalomaniac pilot fish Joe, enabling him to think and speak like a human. Capitalising on his newfound powers, he soon sets up a one-fish state, with himself as a kind of despotic Captain Nemo, supported by a 'dumb but dangerous' shark and bullyboy crabs. For a story about friendship and working together, the characters are cute, the animation pretty well executed, and Rickman is a fine choice to voice the menacing Joe. That said, the film lacks the technical precision of Shrek and the bold, well-rounded characterisation of the Toy Story films. More importantly, it lacks that extra dimension which would engage and entertain the adults in the audience as well as the kids.