The cases of a pair of teen detective brothers and a teen girl amateur sleuth.
Cast:Shaun Cassidy , Parker Stevenson , Ed Gilbert , Pamela Sue Martin , Jack Kelly , William Schallert , Lisa Eilbacher , George O'Hanlon Jr. , Jean Rasey , Edith Atwater , Janet Julian , Robert Karnes , Ron Nyman , Susan Buckner , Anne Lockhart , Edd Byrnes , Ruth Cox , Eric Lawrence
The Hardys investigate the disappearance of their own father, a case involving a haunted house, a graveyard, and espionage.
Nancy suspects something is amiss when an abandoned lighthouse mysteriously activates.
On a trip to a retired police captain's country home, the boys and their friends find him missing and themselves plagued with mysteriously threatening happenings that seem related to an old local legend.
While flying, Nancy sees a car go off the road, and reports it. The bridge is out to that section of road, however, and the police don't believe her. Searching for the car leads her to a young mechanic, and a stolen car ring.
While investigating the disappearance of a missing scientist, the boys begin to doubt their senses when they discover an isolated estate loaded with bizarre illusions.
Nancy's eccentric aunts are selling their property. The day before the deal is reality, a burglar steals all the documents. When Nancy goes to her aunts to explain, she hears mysterious voices in the walls.
While investigating the disappearance of a sound technician, the Hardy Boys find a link to a rock band he was working for.
To raise money for charity, Nancy revives a play in a theater that is supposed to be haunted. Actors from the original cast return to do the play, but they are all acting suspicious, and Nancy is determined to discover the secret of the theater phantom.
Frank thinks he sees a girl who went missing years ago. When he tries to talk to her she claims that she is someone else. Frank and Joe soon find that she's mixed up in something illegal.
During a charity carnival, the wealthy hosts have jewelery stolen from their safe. A young Hispanic friend of Nancy's is accused, after having been seen on the property. Nancy believes the case has more to it than it appears.
While vacationing is Hawaii, the boys are robbed. So they set out to try and find the robbers.
Someone is forcing a famous mystery writer to relive one of his novels before killing him.
The Hardy Boys stumble upon an ancient Asian jade statuette that gangsters are desperate to recover.
A successful football player is being blackmailed into throwing a game, and Nancy must prove his innocence.