A four-book series that shares elements of pulp adventure, treasure hunt stories, and Stratemeyer-esque investigating/snooping, while attempting to update their tropes to fit modern times and be more plausible. Written by Chris Archer, the series consists of The Secret City, Eye of Eternity, Dead Man's Chest, and The Last Clue. All four were published in 2003. All in a day's work -- well, several weeks' work -- for this group of plucky 11-year-olds.