The Hardy boys embark on another puzzling mystery when they try to discover who is stealing rare collections of ancient pirate treasure and smuggling them out of the United States.

The Hardy brothers' visiting Greek pen pal enlists their help in searching for a priceless ancient Greek helmet loaned to and lost by a Hollywood movie company years before. Danger is the name of the game when the Hardys agree to help their pen pal from Greece, Evan Pandropolos, search for a priceless, ancient Greek helmet. Years ago, Evan's uncle had loaned it to a Hollywood movie company for use in a silent motion picture, but the treasured helmet...

Two teenage sleuths help their detective father search for a famous rocket scientist whose disappearance endangers the launching of the Firebird Rocket.

Nancy, Frank, and Joe meet up on the Carolina coast to help a rock musician and a tennis star.

The Hardy boys find the missing deed to an Indians' land, prevent a phony salesman from carrying through a reckless scheme, and help their father solve a top-secret case.

Frank and Joe take a fun trip across country on a new bullet train and end up in the middle of a nightmare where they are blamed for everything, including attempted murder.