An original Sherlock Holmes manuscript was stolen from the Bayport Museum and now pages keep showing up in Frank and Joe's things: their lockers, menus, even the backseat of their car. It's clear someone is out to frame them. But who could it be?
When thirteen-year-old Gerald finds himself the heir to twenty billion pounds from an aunt he never met, he inherits with it a mystery surrounding his aunt's death and various artifacts in the British Museum.
When the plans for the Bat-Wing, a historical aircraft, disappear from the Capitol City Air and Space Museum, eleven-year-old Amal Farah's father is blamed, and it is up to the four young friends to solve the mystery and save her father's job.
"This is a story of stolen violins. It's got mummies, museums, sandwiches, hostages, and a dangerous showdown with the Russian Red Army Choir. Open this book to find out more about my adventures. But beware--this mission is top secret and very dangerous!" -- cover.
When the spacesuit of famous astronaut Sally Ride disappears from a traveling exhibit, Amal Farah, daughter of the Air and Space Museum's archivist, and her three friends, are determined to find the culprit before the exhibit is cancelled.