Three jewel thieves try and find a way to smuggle some expensive diamonds from Hawaii to L.A. That is where Fred and Lamont come in. Fred goes to Hawaii to attend a Junkmen of America convention. The crooks then plan to sneak the jewels on Fred so that he can take them to L.A. without knowing anything about it.
The diamond thieves continue their plot to have Fred smuggle the stolen diamonds into the United States. Freddy Wells sneaks into Fred's hotel room and plants the diamonds in his suitcase. Later, Lamont and Fred discover the diamonds and hesitate to call the police.
During a mishap at the airport Fred accidentally misplaces the suitcase with the diamonds and the crooks start chasing Lamont and him all over Hawaii, trying to get them back. Meanwhile, the cops close on in, but not before guns are drawn on Fred and Lamont as the crooks trap them on a boat.
Fred and Lamont have been busy planting a small garden in their yard when suddenly a professor stumbles in and suggests that they may be sitting on some oil. Later, Fred plants his scarecrow in the garden and actually strikes some oil. This leads to Fred and Lamont to ponder the fact that they may soon be millionaires.
Fred becomes smitten with a woman, Miss Wallace who comes to the Sanford residence looking for a place to stay at the Sanford Arms. Meanwhile, a thief has been spotted in the neighborhood and to get the reward money, Fred lets the cops set up a stakeout in his home. However, Fred is in for a shock since the thief has been in disguise as Miss Wallace.
Lamont's mother-in-law to be is coming to Watts for a visit and Fred is a little concerned about what she's going to think of a common junk man. This leads Fred to decide to create a legacy and tries to set a world's record and get his name in the Guinness Book of World Records. His goal is to be the person to stay awake the longest.
Fred becomes a victim of a con game when, two men convince him to begin a bogus special "Sanford & Son" sales promotion, in which the lucky winner wins $500. However, Fred has no intention of handing out that much bread but unknown to Fred, the con men have rigged the game so they end up being the lucky winners and Fred will have to pay them the money after all.
Fred has been chosen to represent the Watt's businessmen on a community relatives committee and his first official decision is to allow the public library to be open an hour longer. However, his next decision doesn't seem to be so easy to decide after a crooked businessman tries to bribe Fred with $1000 to vote for a building expansion.
Lamont threatens once again to leave the junk business on account that they aren't making much money. However, he also wants to quit and get a full-time job due to his impending nuptials. Fred then hatches a scheme by borrowing money from the bank and pretending that business is picking up big time, while secretly working as a waiter at a restaurant down town.
Fred gets a letter in the mail from someone named Carol who claims that Fred knew her 40 years ago and that she's coming for a visit. However, Fred doesn't recall knowing any Carols and is in for a shock when Carol turns out to be a man. Another shock, Carol claims that he and Fred robbed a bank years ago.
Aunt Esther and Woody have decided to have a baby and set up an appointment with an adoption agency to adopt an older child. However, on the day of a preliminary interview, Woody, so nervous about the prospects of being a father, gets drunk, threatening their chances for an adoption. A heartbroken Esther turns to Fred for help.
Lamont and Esther decide to get the furniture re-upholstered as a surprise present for Fred. In order to get it done, they have to convince him the furniture was stolen. However, when Fred takes it upon himself to report it to the insurance company, he ends up with brand new furniture and Lamont is speechless.
The day has come for Aunt Esther and Woody to meet their son but they are in for a shock when he helps himself to their cash register. Later, Esther is in for an even bigger shock when he announces that he doesn't believe in God. Esther promptly kicks him out and he takes refuge at the Sanford residence.
Lamont runs into Chuck Barris in a parking lot and he generously gives Lamont four tickets to a taping of The Gong Show, which happens to be Fred's favorite game show. Fred decides to try to be a contestant and sets up an act with his brother-in-law, Rodney and Lamont. However, at the last minute, Rodney hurts his back and can't be in the act.
The tax season has come and Fred and Lamont have been going through their inventory to prepare their tax papers. However, Fred gets preoccupied when he discovers Redd Foxx is in town holding a look-alike contest and Fred is certain he will win the contest and the $100 that comes along with it.
Esther has stopped by the Sanford residence to talk Fred into singing for a talent show. Grady is all set to be in the show with a magic act and for his most daring trick ever, he handcuffs Fred and Esther together. The only problem is that he can't understand how to get the two out of this dilemma because the directions for escaping the trick are written in Chinese.
The Sanford residence is in chaos and it is all due to Fred's sudden loss of hearing. Lamont is convinced Fred has a problem, but Fred denies it but Lamont takes him to a doctor just the same. However, after the doctor removes the wax build up, Fred decides to stay "deaf" just a little bit longer in an attempt to hold Donna's attention.
Lamont and his fiancee, Janet are just one step away from the alter. However, a kink is put into their plans when after her wedding shower, her ex-husband John shows up. Meanwhile, Lamont has been having pre-wedding jitters and this just adds to them and Janet finds herself dealing with old feelings she thought had died long ago.
Trying to avoid paying property taxes, Fred registers to become a clergyman for the Divine Profit Church. He appoints Bubba as secretary and Woody as treasurer. However, when the Bishop stops by for a visit, Fred quickly realizes he's put his business in jeopardy thanks to some fine lines in the contact he signed.
Aunt Esther and Woody stop by for a visit and as usual, Fred insults Esther and she responds by promptly hitting Fred in the head with her purse. Apparently the blow to his head is so strong that it knocks him out and when he wakes up begins having memory lapses. This prompts him to make up his will and holds a will reading in the living room.
Fred wants a new stereo and tries to buy one on credit at a local electronics store. He soon discovers that they don't give credit to people over 60. This prompts him to take some action and befriends a rights group, The Gray Foxes and they begin picketing the store until they decide to change their policies.
In order to keep The Sanford Arms, Fred and Lamont must raise $4,000 in a week. They begin to scramble and Fred turns to gambling. First he puts together a card game and plays against a hustler and then he makes a little trip to the horse track and bets on the horses. Finally, a trip to a casino ends with unexpected results.
Fred is tired of everyone walking all over him especially since he proclaims that he built his junk empire to what it is today, thus making him a king of an empire. Bubba suggests that Fred pay money to an agency to have them trace his roots. A couple weeks later Fred is in for a shock, he is a descendant from Jewish African kings.
Lamont treats Fred to a dinner and a concert given by B.B. King. After the show, Fred wants to try to sell his songs to B.B., but fails, however, B.B. offers him a book about his life and why he sings the blues. This leads to an invitation for dinner at the Sanfords. While reading the book Fred panics when he reads the reason why B.B. sings the blues. He explains to Lamont that B.B. lost his girl in St. Louis to a guy who wanted to start a business in California. The girl's initials were EW (for Elizabeth Winfield).
Fred has been neglecting Donna and she decides to investigate and soon discovers Fred has been leading a secret life, not even telling Lamont what has been going on. Donna is convinced that he is seeing another woman but they soon discover Fred is really going to night school to earn his GED diploma, which he never got since he dropped out of high school to support his parents.