Grade: B+

Devotees of the slightly rumpled, veddy British tone and style that marked previous Aardman efforts like “Chicken Run” and “Wallace & Gromit: The Curse of the Were-Rabbit” (as well as the W&G shorts that preceded it) may be somewhat dismayed by this new effort, in which the characters speak with English accents and the character design resembles their traditional clay figurines but the animation is computer-generated by the DreamWorks team rather than the in company’s stop-motion technique, the pace is far more frantic, and the humor not only more machine-gun rapid but also somewhat cruder than usual (some glop, farts and mega-burps). In other words, “Flushed Away” feels much more a Hollywood product.

But though there are signs of a slightly imperfect fit between the very different elements from either side of the Atlantic, the movie proves mostly engaging, the British whimsicality happily trumping the American tendency toward empty flashiness. The plot centers on Roddy St. James (voiced by Hugh Jackman), a pampered pet mouse left alone when his upper-crust Kensington Road family goes off on holiday. Much to his horror, the house is invaded by a gross sewer rat named Sid (Shane Richie), whom he tries to dispose of by flushing him down the toilet, only to find himself flushed instead. Below the human surface he discovers a bustling rat community that’s like a mini-mirror image of old-time London. There Roddy encounters a lower-class female trawler captain named Rita (Kate Winslet), whose sewer-sailing boat might be his ticket back home; the relationship between them starts out, conventionally, as hostile but turns more and more romantic as the plot progresses.

In truth Roddy and Rita are a pretty bland couple, and despite the enthusiastic delivery of Jackman and Winslet, the material that focuses on them is less than enchanting. But happily they’re surrounded by a wide cast of supporting characters that are mostly far more fun. That doesn’t include Sid, who’s loud and vulgar and quickly tiresome; but he disappears quickly, reemerging only briefly toward the close. Far more enjoyable are the villain, The Toad, a Sydney Greenstreet-style figure (a discarded royal pet, no less–allowing some good Buckingham Palace gags) voiced with magnificent grandiloquence by Ian McKellen, who plans to destroy the mouse community; his supercilious French cousin Le Frog (Jean Reno), whose presence allows some good Gallic jibes, one involving a mime; and his klutzy lieutenants Whitey (Bill Nighy) and Spike (Andy Serkis). But beyond these main figures are a slew of minor ones that regularly earn laughs–Rita’s eccentric family, voiced by such first-rate talent as Kathy Burke, David Suchet and Miriam Margolyes (whose misidentification of Roddy as Tom Jones gives Jackman an opportunity to show off his singing talent), Le Frog’s band of inept henchmen, and a gaggle of musically-inclined slugs who interrupt the action periodically with sung commentary in what’s probably the movie’s best running gag.

In fact, even apart from the slug obbligato, the musical choices made throughout “Flushed Away” are among the movie’s biggest strengths. They complement the visuals, which mimic the slightly awkward, homely Aardman style in terms of both characters and backgrounds despite their CG origin, very nicely.

“Flushed Away” ends, of course, with a big finish in which Roddy must not only decide whether to stay in his plush surface home or return to the sewers–not only because he must foil The Toad’s wicked plot but because he’s attracted by the tug of a rodent family as opposed to a human owner. And it will come as no surprise to learn that he proves his mettle, even if the precise manner of his doing so seems a bit muddled in the narrative department. More surprising is the fact that “Flushed Away” deserves a far happier fate that the title would suggest. It doesn’t match the low-key charm of “Wallace & Gromit,” but the combination of Aardman eccentricity and antic DreamWorks energy proves a far more palatable mix than one might have anticipated.