Revealing too many details of the movie might spoil it for you; it's best experienced with as few expectations as possible. The basics: it's a modern, almost dialogue-free French/Belgian/Canadian animation feature from 2003 that combines lovingly detailed, often stunningly grotesque hand-drawn characters with some amazing effects that could only be generated by a computer, resulting in the best of both worlds. (The art, storyline and attitude would make it a perfect fit for our friends at Ideas In Animation, who scour the world for bizarre and poignant cartoon shorts from all over for Nik Phelps to apply his musical magic to.) The movie is probably too much for small children (the Fred-Astaire-eaten-by-his-own-shoes bit at the very beginning will be enough to give the more sensitive little ones nightmares...not that I haven't seen far worse and less clever stuff on Adult Swim), but both artistically-inclined adults and teenagers who enjoy a good gross-out joke (and vice versa) will dig it.
Without giving too much away, here are some of the things you will see: a devoted grandmother, a deadpan cipher of a grandson, a strange trio of aging avant-garde Andrews Sisters types, the Tour De France, a breathtaking ocean journey, many entertaining violations of the laws of physics, a hint at what Pink Floyd's abandoned Household Objects album might have been like, a glimpse into a horrific underworld of sadistic exploitation, a look at Americans as the French see us* (perhaps we should cut back on the hamburgers a bit), a dog's increasingly mad and nightmarish dream sequences, and a truly ridiculous chase scene. Oh, and the frogs.
*Considering the year that it was made, the jab at American culture from a French animator is probably not so surprising.