A young woman has gone missing and Cannon is hired to find her. The four men responsible for her death frame a young black man for it and Cannon sets out to clear him.
Cannon flies to Tampa, Florida, to find a man who abruptly withdrew a large sum of money from his bank account and then disappeared with two gunmen on his heels.
A desperate woman fingers Cannon as her brother to a hit-man who is waiting for him at an airport in order to save her brothers life. Cannon must investigate in order to the life of the woman's brother as well as his own.
Cannon is hired by a man who hired a hit man to kill him and even made the killer his beneficiary. Now he has decided he wants to live, but the hit man refuses to give up.
An Italian businessman with close ties to his government calls on Frank Cannon when his daughter is kidnapped in the United States and held for ransom for the release of terrorists currently imprisoned in Italy.
A dying prisoner, a former hit man, confesses to Cannon that he killed Frank's wife and child 14 years ago when Cannon was a cop. Cannon investigates to find the person responsible while trying to control his desire for revenge.
Frank Cannon and Barnaby Jones investigate the rape and murder of a young lawyer who was about to blow the whistle on her corporate employer. But they're investigating for different clients and from different angles.
A doctor treats a diabetic in the emergency room and she then dies. He claims that the patient was wearing an indicator bracelet that has seemed to have vanished. Cannon is hired to investigate.
Cannon is hired to find a popular recording artist who he believes is being held against her will. But when he finally finds her he begins to understand that there is a much more sinister reason for her being kept from the outside world.
Cannon teams up with former officers who were on the force the same time he was. Their task is to find another colleague who they believed was dead for the past eight years, but now suspected of killing those he was involved with in crime.
An old friend hires Cannon to bring back the body of his dead son from Mexico and to find his killer. Cannon agrees, but he uncovers a few surprises in the process.
Cannon investigates on the behalf of a oil executive who claims he is being framed for fraud and embezzlement. But he runs into heavy resistance in his investigation from the corporations domineering female president.
Cannon unravels a murder plot that was made to look like it involved the Chinese Tongs gang. But the intended victim turns the tables on the real man behind the plot and tries to eliminate Cannon in the process.
Cannon and a female vice squad officer who's on leave after being viciously beaten while undercover posing as a prostitute go after this same man who has previously beaten prostitutes to death while playing the music "The Wedding March".
When the son of a famous actress disappears the police think its another instance of his recurring drug problem. Cannon is hired to find him, but no one is telling him the whole truth.