(From the publisher):
While visiting an art school in the Mexican town of San Miguel de Allende, Nancy stumbles across an operation dealing counterfeit U.S. green cards. The Hardys are in Mexico City, investigating the theft of a priceless Mayan jade mask. Nancy and the boys are about to take an unguided--and highly dangerous--tour of the smuggler's craft.
Original title: Passport to Danger
Genre: Fiction→ Children & Young Adult→ Mystery