The wildly uneven French writer/director/producer Luc Besson has a fondness for life outside the margins of conventional society: the neon-lit labyrinths of the Paris Metro (Subway), the pristine depths of the ocean (The Big Blue). His latest flick finds him subterranean once again, this time in a fantastical universe where elves and fairies so small they are invisible to human eyes live in harmony with nature. Adapted from his own series of children's books, this live-action/computer-animated hybrid follows ten-year-old Arthur (Freddie Highmore), who, in order to save the home he shares with his somewhat addled grandmother (Mia Farrow), must decipher his grandfather's diary. Following the clues, Arthur, now a 3-D animated figure sporting cool shades and spiked hair, enters the mythical Seven Kingdoms, where he joins forces with a sexy CGI princess (voiced by a delightfully unrecognizable Madonna) and her chubby, rubber troll of a brother (Jimmy Fallon) as they battle the evil Lord Malthazard (David Bowie) for buried treasure. Predictable and overly busy, this sci-fi adventure should nonetheless appeal to computer-game-savvy tots, especially those familiar with the source material.