One Sparking, City! One space-age tower! One mysterious Box! A stash of silver dollars! And a sky-high adventure! Christina, Grant, Mimi, and Papa head for Seattle’s famous Space Needle, and end up in a "towering" mystery full of curious tokens, shiny silver dollars, suspicious characters, and words of warning from someone – but who?? And why??

This mystery incorporates history, geography, culture and more! Fun activities, built-in book club and SAT words are in each book.