After Joe Hardy's fiancée is killed by a hit-and-run driver, the FBI won't let the police arrest the man until their own case against him is finished. Joe takes the law into his own hands and goes undercover as a rich gambler with underworld connections.

Nancy and famous criminologist Arlo Wetherly find mutilated photos of themselves.

Joe Hardy is still haunted by memories of his dead fiancee, but has to focus his mind on the case when Jocco's girlfriend overhears him talking to the police on the phone. Meanwhile, Frank Hardy tries to help Joe by going undercover too, but Jocco finds out and traps Frank in a shark-infested area.

Allison Troy's Transylvanian rock concert has locals fearing a reawakening of their most notorious denizen.

Townspeople revile a psychically gifted girl (Melanie Griffith) who has a mysterious tie to an eerie mansion.

Frank & Joe team up with Nancy Drew again in Los Angeles to attend the 14th Annual Detectives' Convention at a TV & movie studio. Joe pursues an illusory figure through the back lot of the studio's stage 24.

Frank and Joe are invited to join a charter flight which passes over the Bermuda Triangle.

Joe awakens in a Hong Kong hospital and is led to believe that he has been comatose for a year and his father and brother are dead.

When the daughter of a Russian official defects to the U.S. by hiding in one of the rock band Bread's speaker cabinets sent to Hawaii, the Hardy Boys must track her down before the KGB does.

While in New Orleans for Mardi Gras, Frank and Joe's wallets are stolen; Nancy works under cover as a magician.

Joe and Frank Hardy go to London to find their missing father, but when Frank goes missing as well, Joe and an agent from the British Ministry must find a traitor together.

Frank and Joe Hardy are assigned to go to Puerto Rico to protect a senator's daughter from an international blackmailer known as the Scorpion.

Marla falls for an American agent, but Soviet killers pursue her.

Nancy and the brothers team up to find Fenton Hardy, who disappeared while investigating a series of European art thefts.

A woman executes a securities scam from Atlantic City casinos using a code that the Hardy Boys must break.

The Hardy boys spot peculiar, alien-like people on an old missile site being guarded by federal agents.

Nancy is determined to restore the honor of a dear old gentleman who claims to be Santa Claus when he is accused of burglary.

The lead singer of a rock band runs down investigative reporter Jerry Morgan.

While windsurfing in Hawaii, Frank tries to rescue a girl named Maryann (Maren Jensen) who disappears and is claimed to be dead. He then begins to become obsessed with finding out what happened to her, but someone, who is also on her trail, is watching him.

The boys go under cover at a New England college where three coeds have been kidnapped.

Frank and Joe Hardy journey from the South of France to the Caribbean to find a girl who disappeared while hunting for pirate treasure.

While in Mexico trying to solve the mysterious kidnapping of their father, Frank and Joe discover hang gliding and dangerous enemies.

Nancy goes under cover to keep a light-fingered tennis star out of trouble.

The brothers find a dead man in a coffin in their hotel room.

In Greece to investigate drug smuggling, the Hardy Boys pose as archeology students on a dig for the lost city of Atlantis, but they are dogged by suspicious accidents and a dead body.