Jon (Meyer) is a cheery young guy living in a gorgeous house with his fat, lazy cat Garfield (voiced by Bill Murray--and no, the humans can't hear the animals' voices). Jon has a schoolboy crush on the local veterinarian hottie (Hewitt), and adopts the homeless pooch Odie to impress her. But this of course sends Garfield into spasms of panic as he plots how to get rid of the dog. Then Odie's kidnapped by a nutty TV presenter (Tobolowsky) and only Garfield can rescue him.

There's a consistent stream of humour that at least keeps our interest, even though the writers haven't bothered to be either inventive or clever. The comedy and plot are worn out before the movie even starts--derivative and predictable, although there are a few sharp zingers here and there, mostly due to Murray's vocal work (everything else is pretty bland). Alas, there are frequent corny action set pieces and a couple of astonishingly ill-conceived bits, the most gruesome of which has Garfield crooning a bluesy lament about Odie to the tune of New York State of Mind.

Oddly, all of the animals in the film are real except the extremely cartoonish Garfield. The effects that create him are sometimes impressive, but mostly fairly clunky, especially since we can never accept him interacting with the actual dogs, cats and rodents he enlists to help him--they're genuine but he's not! It's also strange that Odie is the only animal who never speaks. And that the humans are all so insipid. So when Murray gives one of the rather weak jokes an extra vocal kick, we find ourselves chuckling almost in desperation. And as a result, the film is surprisingly watchable. But only just.