Three investigators

Three young detectives travel abroad to solve a mystery involving a silver spider and a political plot that endangers the life of a young prince.

Jupiter Jones, Pete Crenshaw and Bob Andrews are involved with a bank robbery, a lady troubled by gnomes, and an attempt to send the boys to slavery in the Middle East.

Three junior detectives solve a mystery involving a collection of antique busts, a legacy, a strange letter, and a red ruby.