Saul Garamond comes home to his London apartment to find his father murdered and himself under arrest. While grieving in his jail cell, he is broken out by the stinking, shadowy King Rat, who takes Saul to the world beneath London's streets before revealing to him his own half-rat heritage. King Rat means to enlist Saul's aid against their oldest enemy, the Piper, who long ago embarrassed the King and stole the children in Hamelin, and has come again to do the same in London. This time, however, the rats have half-human rat-prince Saulwho is immune to the Piper's tuneon their side. If King Rat sounds a little too cute, it's because the book takes its cues from two of fantasy's most sugarcoated themes, the Lost Prince and the x. But it's somewhat grittier than that; the Prince doesn't usually eat garbage every few pages or spend most of his day wading through sewage. China Miéville blends a lot of good, solid folkloric material with a good deal of contemporary urban paranoia and drum-and-bass music, the multi-layered richness of which the Piper seeks to use for his own ends. It's ambitious, to be sure, and involved at timesit would help to know something about Cockney rhyming slang, the layout of London and its environs, and jungle musicbut the book can easily be enjoyed by anyone with a love of good, gritty make-believe. King Rat is a strong first novel in the quirky sub-sub-genre of subterranean fairy tales that, with such recent good books as Lisa Goldstein's Dark Cities Underground and Neil Gaiman's Neverwhere, looks less cute and more promising by the minute.