(From the publisher):
Chet Morton's cousin, Vern, is on his way to California to find a rare and valuable coin mysteriously missing from his uncle's bank vault. When he stops in Bayport, his brand-new car is stolen. The Hardys take on a double mystery-and double danger as they head for the West Coast to investigate this sinister mystery.
Original title: The Vanishing Thieves
Genre: Fiction→ Crime and Mystery→ Detective Story and Detectives
Fiction→ Children & Young Adult→ Mystery
Fiction→ Children & Young Adult→ Suspense/Thriller