Honey, I shrunk the cartoons

With its unconventional, buck-toothed heroine, the cartoon comedy The Wild Thornberrys has provided some of the best TV of recent years. So why doesn't the movie version measure up? Robert Hanks reports

An elderly relative of mine once complained to the Broadcasting Standards Council – and had the complaint upheld – about a sketch on a Channel 4 comedy show that spoofed Scorsese's GoodFellas: his complaint centred on what he saw as the unnecessarily obscene language used. When he told me about this I was surprised, because not long before we'd watched the film version of David Mamet's Glengarry Glen Ross on video together, and he had taken the salesmen's torrents of four-letter words without blinking; in any case, he liked Scorsese films. When I put this to him, his answer was, "Yes: but you don't expect the same things from films and television."

Which brings us to the thoroughly wholesome world of the The Wild Thornberrys, the most consistently intelligent, funny and loveable cartoon series to hit the small screen in some years – and coming soon to a multiplex near you. In case you don't know, the series revolves around the adventures of the Thornberry family as they travel the world in their mobile home, filming wildlife documentaries for cable TV.

The protagonist is 12-year-old Eliza Thornberry – gawky, pigtailed, bucktoothed, but smart and adventurous. What's more, Eliza can talk to animals – a gift bestowed by an African shaman in gratitude for being rescued from a life trapped in the body of a warthog (look, I said it was intelligent and funny; nobody mentioned plausibility). Unfortunately, for vague magical reasons, Eliza must keep her gift secret from all other humans, or lose it forever.

Eliza's gift is the shtick for The Wild Thornberrys, and the main plot-motor; what makes the cartoon engaging is the interaction of the Thornberrys – affectionate but decidedly tetchy, a nuclear family gone critical from spending too much time together. There is Eliza's dad, Nigel, a guffawing Englishman, who fronts the documentaries; her mom, Marianne, a sensible, sharp-witted American, who films them; her slouching, vengeful teenage sister Debbie; and her adopted little brother Donny, a dreadlocked boy brought up by orang-utans and exuberantly oblivious to the constraints of civilisation. As a counterpoint to Donny there is Darwin the cowardly and fastidious chimpanzee, a kind of hairy C-3PO, and Eliza's best friend.

The Wild Thornberrys Movie brings the familiar ingredients of the television series to the boil: shocked by Eliza's indifference to danger during a clash with poachers on the Serengeti, Nigel and Marianne are persuaded to pack her off to boarding school in England; but with Darwin's help, she runs away and flies off to the Congo to save her beloved animal friends.

When the film was released in the US before Christmas, a reviewer for The Washington Post declared that it was in the same league as Toy Story or Shrek: high praise indeed, but wrongheaded. This is not so much a matter of quality (though to my mind, the movie version lacks the compactness and wit of the best of the television episodes), as one of kind. The Thornberrys isn't playing in the same league as those smooth, classy mega-hits; I'm not even sure it's playing the same game. Even on the big screen, it is too whimsical, too consciously domestic in mood and scale for the comparison to make sense: it's like comparing Porridge with Escape from Alcatraz.

Place The Thornberrys or Rug Rats – both made by the animation company Klasky Csupo – alongside mainstream Hollywood animation, and you realise how far the American cartoon tradition, even at its most fantastic, is in thrall to realism. Not long ago, I saw a television documentary in which one of the animators of Monsters, Inc. demonstrated how he watched himself in a mirror as he delivered lines, so that he could capture expressive movement.

The difference between Klasky Csupo and other animators is partly just about difference: recognising that they couldn't compete with Disney on its home turf, they set about trying to be as distinctive as possible. As Gabor Csupo told me on the phone from Los Angeles, their main influences are European rather than American: he was born in Hungary, in 1952, and after four years in the Pannonia animation studios, escaped to the West in 1975; and many of the animators they employ are from similar backgrounds.

Being European means making characters more "offbeat", more graphic. The animals – aye-ayes and dugongs, reindeer and Komodo dragons – are more or less realistic, though with some stylisation just to harmonise things; but people are gargoyles: pipe-cleaner limbs, eyes like saucers or pinpricks, noses that jut out for yards, or disappear into tiny buttons. Debbie Thornberry's eyes, thick with mascara, finish somewhere off to the side of her head; Nigel's magnificent proboscis appears to have been grafted on from Mr Punch or some anti-Semitic caricature; and as for Eliza... According to Csupo, "We got a lot of complaints from Nickelodeon [the children's network that first broadcast The Wild Thornberrys] in the very beginning that she's so unattractive, kids aren't going to like her, we should lose the braces and stuff."

It is interesting, and mildly saddening, to observe how this small-screen idiosyncrasy has been muted by the different expectations of the big screen. The most glaring change is in the background: the brightly coloured, flatly drawn landscapes have been replaced by rich, complex washes of colour, giving you something much closer to a real wildlife documentary; and some segments involve computer-generated imagery, with its unnatural and off-putting smoothness of motion.

This feels like an unnecessary compromise to me, but Gabor Csupo insists that such alterations are required: "On a big screen you are seeing shortcomings... Generally we are having to put more details, more shadows, more textures into the background. The budget a minute is a lot bigger than for TV, so obviously all that money has to go on the screen. And the African vistas deserved that kind of scope."

Another intriguing change for the big screen involves the shaman who gave Eliza her powers, who on the big screen loses a potbelly and a hook nose to rival Nigel's. Perhaps there were good visual reasons for this; but I suspect the change is connected with the fact, proclaimed in the press notes, that to ensure that sufficient respect was paid to African characters, they not only employed experts on African culture, but an expert on African-American race relations.

We're told that the writer regarded it as an honour to have her dialogue translated into the actual language spoken in the Congo. Well, Rugrats in Paris had some dialogue in French, but I don't recall any statements about what an honour it was to have it translated into the actual language spoken in France.

The reason I'm faintly annoyed by this is that no such respect is paid to the sensibilities of the English audience: in the boarding-school scenes, Hollywood has once more reduced English life to tight-lipped, emotionally repressed upper-class idiocy. This is a shame because one of the wonderful things about The Wild Thornberrys has been the way that the overemotional, hyper-enthusiastic Nigel (a terrific vocal performance by Tim Curry) reverses the usual Anglo-Saxon stereotypes. In some unexpected ways, moving to the big screen has shrunk The Wild Thornberrys.

Meanwhile, they may have come to the end of their television career, after some 90 episodes; but this summer sees another movie: The Rugrats Meet the Wild Thornberrys. If you have children, you are unlikely to have any choice in the matter. You might as well get used to the Thornberrys now.

'The Wild Thornberrys Movie' is released on 7 February