Three real estate crooks die horrible and mysterious shellfish related deaths, and McGarrett and the others must establish the link between them, and who has reason to want them dead.
Julie, Link and Pete break down in the desert during a sandstorm and seek shelter in an abandoned mine. An old man embittered by the death of his son in the war who hates hippies then sets off dynamite and traps the trio inside.
Lucy Carter, a widow with two teen children, takes a job as a secretary for her stuffy brother-in-law.
All about Joe and Hoss' visit to a small Mexican town named Agua Santos, which seems to have some rather peculiar laws. The two Cartwright boys soon find them in pretty deep trouble for breaking ""laws"" that barely would pass without notice stateside.
Serena returns for the last time and babysits with Tabitha and Adam. Larry comes by to return a golf club and Serena does an Abby Cunningham on him. Larry hurries off, but not before Serena gives him a pill to be young and active (pre-Viagra!). It makes him younger, all right, by ten years! Larry gets even younger and younger and everyone is very worried about him. Serena gives him an antidote which turns him back to normal.
The Doctor is convinced the Ice Warriors are trying to sabotage the conference but his attempts to prove it see him accused of sacrilege.
Bess gets top marks for a report she wrote for school, and Phyllis pressures her to write a book based on it, calling on Mary for help.
The Bunkers are alone for eight days while Mike and Gloria are spending a week at a commune.
Fred and Lamont buy a load of copper from a man that has been stealing copper in the neighborhood. The man is late for a meeting with Lamont at the diner because he is ripping off the Sanford plumbing pipes, which he then sells to Fred and Lamont.
Chris and Tracy invite a street worker into their home. He says he is a world-class Russian painter and says he can paint a work of art on their garage door. The completed picture is a nude woman that all the neighbors complain about.
Brett's relatives are being killed off one by one, so Brett and Danny decide to find the killer before he gets to Brett.
Hannibal Heyes and Kid Curry, two of the most wanted outlaws in the history of the West, are popular "with everyone except the railroads and the banks".
The small daughter of a friend of the Chief's dabbles in witchcraft, and becomes convinced that she is responsible for the death of her parents' landlord. Taking to the case to show her that the truth is otherwise, Ironside discovers that the man arrested for causing the death might be equally innocent.
An eccentric billionaire is accused of murdering a business associate, but will not leave his boat to defend himself against the accusations, allowing his associates to declare him mentally incompetent.
A Vietnam veteran returns to the police force with questionable ideas of dealing with dissident ghetto residents.