Who knew that bears and mice were such mortal enemies? Well, it will come as no surprise to fans of the children's books by Belgian author and illustrator Gabrielle Vincent (1928-2000), but first-timers will find this Oscar-nominated animated film to be a worthy introduction to her beloved characters: Ernest the bear, a brash, grumpy, sometime street musician, whose perpetual hunger drives him to extremes and even puts him at odds with the police; and Célestine the mouse, a precocious and resourceful tot with a fearless streak that gets her into and out of one predicament after another. Said hatred runs deep on both sides, mostly due to the mice's crafty habit of emerging from their subterranean empire to steal, in their infinite wisdom, the teeth that bear cubs leave under their pillows. As fate would have it, the pearly whites of their aboveground adversaries are without equal, and the rodents' chief industry involves making dentures for a diminutive species that depends on proper mastication for survival. Fortunately, the title characters do not subscribe to the enmity of their peers, at least not after their first encounter: Célestine wakes in a snowy dustbin the morning after a botched robbery and, thanks to the aforementioned spunk, avoids becoming Ernest's breakfast in a moment that redefines "meet cute." What follows is an amusing game of bear-and-mouse as Ernest and Célestine forge an unlikely alliance in defiance of their respective communities, eventually hunkering down in Ernest's hilltop hovel, out of sight of the long claws and paws of the law who are determined to make an example out of them. Although they're now outcasts, they discover they were made for each other: Ernest nurtures Célestine's love of drawing (unlike Hermey in Rankin/Bass' Rudolph the Red-Nosed Reindeer, she has no interest in studying dentistry), while Célestine nurses her ursine patron back to health from a nasty cold and shelters him from an annoying hole in the roof. Their relationship veers from father/daughter to mother/son to brother/sister, but they look out for one another like Best Friends Forever. All good things must come to an end, however, and our heroes are ultimately discovered and subjected to a sensational trial of the century. The fact that they narrowly escape being ground to a furry pulp beneath the creaky, xenophobic wheels of justice is predictable, but that doesn't make the fiery, nail-biting finale any less enjoyable. All in all, this is old-fashioned, two-dimensional fun, directed by Stéphane Aubier, Vincent Patar, and Benjamin Renner with simple watercolor animation that's easy on the eyes (The Triplets of Belleville's Didier Brunner is a producer). The fairy-tale script, by French novelist Daniel Pennac, is well-paced and imaginative, though it should be noted that Vincent refused several offers to let her work be adapted into a film while she was alive. But the crowning achievement is that the main characters are easy to root for and sweet without being saccharine, making this the kind of buddy picture that audiences of all ages can sink their teeth into.