The Pandowdy family, from Wisconsin, are in beautiful, sunny Mexico for a vacation. While looking for shells on the beach, the youngest daughter finds a shell that makes a rattling sound. The shell reveals a gold chain and a mysterious dark coin with the name, Quinta Rios, etched upon it. They try to return the trinket to its rightful owner and find themselves knee-deep in a kidnapping ring run by 20th Century wannabe Aztec warriors serving the god, Huitzilopochtli. Blood-thirsty would-be Aztec priests, the exotic coastal areas of Mexico, and world-famous Aztec temples and ruins, provide the background for the girls and their friends as they attempt to unravel the mysterious disappearance of local children, all the while fighting to keep from becoming sacrifices themselves! Its a fun, rough and tumble, mystery headed up by the four Pandowdy girls, Emma, JoJo, Loobie and Kootchinelli, a big boy-man named, Tonto, and a cool kid named, Rufio.