The Walt Disney Corporation must pray nightly to their gods (most probably The Almighty Dollar) thanking them that Pixar Animation Studios exists. While over the last decade Disney's animations, despite being where the company made their name, have been decidedly lacklustre, and have had a subsequently poor showing at the box office, their partner has wowed the world with a series of humorous, inventive, beautiful and hugely entertaining computer-generated masterpieces, featuring impressive voice talent and even more impressive visuals.

Since taking the world by storm with their debut feature Toy Story, Pixar have become a household name, almost as well known now as Disney itself, and have made themselves (and Disney) a huge pile of cash in the process. You only need to have walked past a Disney Store while Finding Nemo, and Pixar's previous film, Monsters, Inc., were being promoted, and seen the thousands of cuddly Mikes, Sullies and Marlins almost falling out of the door, to know how popular their films are, and how important Pixar is to Disney. It is not a relationship Disney are going to want to end any time soon (though Pixar themselves may feel differently - it?s not quite clear what they are getting out of their deal with The Mouse House, other than the opportunity to give Disney a large whack of their hard-earned moolah).

And Pixar's magic doesn't look like failing, either. Quite the contrary. By the time Finding Nemo opened on these shores in October 2003, it had already grossed almost $350 million in the United States, making it the most successful animated feature of all time. Pixar films are now almost guaranteed to be a success, and, unlike The Matrix Reloaded, which rather pleasingly took almost $60 million dollars less in the US than Finding Nemo, the hype is fully justified.

Finding Nemo is the story of a clownfish called Marlin (Albert Brooks), and his son, and only child, Nemo (Alexander Gould). Traumatised by the ingestion, and subsequent digestion, of his wife and all bar one of his children by a predator, Marlin has become a doting, but over-protective, father to his remaining child, and has himself become afraid of the open sea, and any hint of danger. Taking Nemo to his first day of school (a school of fish - oh dear oh dear), Marlin is very reluctant to leave his son, but eventually manages to do so. However, on hearing that his first scholastic activity is an excursion to the edge of the reef where they live (the 'drop-off' into the open ocean), Marlin panics and sets off after the class. Embarrassed by his father in front of his new classmates, and eager to prove that he can do things for himself, Nemo sets off to 'touch the big butt' (a boat, in case you were wondering), gets himself caught by a diver, and is taken away to live in a tank in a dentist's waiting room in Sydney.

Distraught, Marlin chases after the boat, but simply cannot keep up. He does have one clue, though, to his son's whereabouts - one of the divers has dropped a mask, and there is an address written on the band. But he can't read English. What he needs is a translator. But where to find a translator in the ocean? Gee, what a predicament. Rather fortuitously for Marlin, he soon meets a ditzy blue fish called Dory (Ellen DeGeneres) with a major amnesia problem, but the useful ability to read. (Those zoologists among you who are interested to know Dory's species will be pleased to learn that it is Pisces MacGuffin.)

Having deciphered the address on the diver's mask - 42 Wallaby Street, Sydney; a nice nod to Aardman Animations' Wallace & Gromit, who live in West Wallaby Street - Marlin and Dory set off for Australia, many thousands of miles distant from their reef. The two new buddies are variously helped and hindered along the way by, among others, a group of reformed sharks, led by Bruce (Barry Humphries), who have forsworn eating other fish ("Fish are friends, not food"), a pelican called Nigel (Geoffrey Rush), surfer dude turtles (and please disregard any ignorant rubbish you may read on other websites (Empire particularly) stating that these turtles are stoners - they are surfers, nothing more. Pixar are far too responsible to include drug-abusing characters in their child-oriented fare) and a wise-ass shoal of fish who do fish impressions (don't ask, just watch).

In the meantime, Nemo is making friends in the dentist's fish tank with a group of slightly unhinged co-captives led by Gill (Willem Dafoe), who, in the best traditions of The Great Escape, is constantly trying to obtain his freedom from the tank, and the possible, dreaded, attentions of the dentist's niece, Darla. Unfortunately, one of Gill's escape plans, and central tenets of belief, that all drains lead to the sea, may cause your children to want to indulge in a spot of piscine emancipation, so if you've got kids, and fish, keep a close eye on both when you get home?

Many of the film's events contain morals and lessons, most of which will be accessible to, and worthwhile for, the kids watching, and some, particularly the themes of a parent struggling to 'let go', may be poignant for the parents in the audience. And while it is a reasonable fear that this could lead to over-sentiment, apart from a few small dips into this area, Finding Nemo keeps the fun and laughter pretty much constant. Anyway, while the kids learn life lessons, you can be looking out for the references to other movies, of which there are many; from Bruce the shark (the nickname of the rubber predator from Jaws) to Monty Python And The Holy Grail ("swim away, swim away"), with pleasing riffs on Psycho, The Birds, The Terminator and others along the way.

Lacking the impressive voice talent of the Toy Story movies, and the excellent comic pairing of Monsters, Inc.'s John Goodman and Billy Crystal, Pixar have nonetheless assembled a really rather good cast for Finding Nemo. Albert Brooks (well-used to cartoon voiceovers after several guest stints on The Simpsons) is engaging as mollycoddling father Marlin, Oscar winner Geoffrey Rush as a pelican, Willem Dafoe as maritime escape officer and Ellen DeGeneres as the forgetful Dory. Surprisingly, it is DeGeneres who is the star of the show, getting most of the best lines ("uhhh? the sea monkeys have my money") and having apparent free reign to make comical noises when attempting to communicate with whales.

Where Pixar have excelled, yet again, though, is the lush visuals. The use of colour is magnificent, with some truly gorgeously-rendered, vibrant reefs, along with the huge variety of maritime wildlife on display. The use of movement is spectacular too, and it only adds to the enjoyment of the film if you realise just how difficult it must have been to mimic the flighty movement of shoals of fish, and just how well it has been accomplished. One problem, alas, is an unavoidable consequence of the film's setting. Reefs aside, the ocean is just an awful lot of featureless water, and at times, even though the brightly coloured characters fill most of the screen, the settings can seem very bleak and spartan. But this can't really be considered a fault, since Pixar didn't design the Earth's seas.

Though not as fun as Monsters, Inc., nor as clever as Toy Story, Finding Nemo is still immensely enjoyable, and Pixar continue to show they are the leading lights in the world of computer-rendered animation. Disney better hope Pixar don't decide they are better off alone.

From my octopus's garden beneath the waves, I award this film 4 out of a possible 5 units of fish-filled goodness. Oh yeah - stay for the length of the credits - it's worth it. And expect Robbie Williams' rendition of Beyond The Sea to stay in your head all night!