The final show of the series. Elly May's intended husband may win out in marrying her for her money. Hathaway tries to expose his plan to Drysdale, Granny and Jed. Jethro may wed as well but may or may not return to California.

Unemployed actor Dick Bremerkamp expands his repertoire of guises as he works his way into the Clampett fortune.

Dick Bremerkamp, a penniless actor, learns the Clampetts are millionaires and courts Elly.

Jethro's childhood sweetheart Louellen comes to visit the Clampetts, who believe that she wants to marry Jethro. Jethro panics and runs away because he thinks that marrying a hillbilly girl like Louellen would damage his image as a sophisticated international playboy. Elly May starts her new job as a secretary for Mr. Drysdale, who is nice to Miss Hathaway only when Elly May is around.

Elly May decides to actually start working at the bank and to move in with Jane Hathaway to her apartment. While Drysdale tries to persuade Phinney the landlord to sabotage them

Life gets back to "normal" with the Clampetts, but Jethro, Mr. Drysdale, and Banzai have adjustments to make.

Miss Jane and the women continue their crusade against male chauvinism, but they must overcome centuries of Japanese culture, Mr. Drysdale, and Jethro's giant "intellect".

Jed and Jethro get help from a karate expert's geisha girls to run the mansion, while Granny, Elly, and the bank's secretaries all move into Miss Jane's small studio apartment as a headquarters for their cause.

Miss Jane and the bank's secretarial staff foment a revolution against Mr. Drysdale's repression that spills over into the Clampett's family life.

The women employees at the bank rebel against Mr. Drysdale's unfair work practices and he locks them in his office. The Clampetts are caught in the middle where Jed tries to hear both sides but Granny takes action.

Mr. Drysdale's latest ploy, involving duping the Clampetts into believing that the annual running of the grunion fish is an invasion by the people of Grun, backfires when Miss Hathaway organizes the female bank employees in protest.

When the Clampetts learn that the grunion are due on the California coast, and having no idea who or what grunion are, head down to the beach to defend it from invasion.

Mark finally convinces Granny he's all human, then sets about resigning his Navy commission to pursue oceanography research. Mr. Drysdale creates a diversion to keep Jed from funding Mark's new ambitions.

Granny and Mr. Drysdale are desperate for different reasons. Granny hopes that if Mark tastes Elly's cooking, he will leave. Mr. Drysdale dresses as Napoleon Bonaparte to keep Jed from investing in Mark's ocean project.

Shorty returns and Granny convinces him to pretend to be Elly's boyfriend to drive Mark away. Mr. Drysdale tells Jed that the idea of him giving millions to the ocean project has made Miss Jane mentally unstable.

Mark shows Granny and the rest of the family a film about his navy job to help her understand his frogman activities. She remains unconvinced. Mr. Drysdale is alarmed that Jed wants to invest millions in underwater farms.

Granny remains convinced that Mark is turning the rest of the Clampetts into frogs. She takes the amphibians to psychiatrist Dr. Klingner in the belief he is able to return them back into humans.

Granny goes to extreme measures to keep Elly from Mark, who she's convinced is turning the family into frogs. Mark tells Jed more about his naval duties, especially about harvesting food from the sea.

Granny is desperate to keep Mark from being a frog so he can eventually marry Elly. She heads to the bank, believing that if Miss Jane kisses the frog, it will become human again. Jane refers her to psychiatrist Dr. Klingner.

Elly continues dating Navy man Mark. Granny objects, convinced he is part frog. While Jed tries to keep Mark from eating his daughter's cooking, Granny works to find a cure for his amphibious ways.

Rev. Matthew's lookalike brother Mark, a Naval officer, shows up to meet Elly May. The two head to the cement pond, but later when Granny sees Mark in his diving gear, she is convinced that the water turns him into a man-frog.

After Honest John explains to Jed why they couldn't visit the White House, he sells them other Washington landmarks each conveniently only $1 million. Mr. Drysdale finds out and sends Miss Jane to bring the Clampetts home.

The Shafers meet the Clampetts in in Washington D.C. to "broker" more prime real estate.

The Clampetts are determined to help the nation solve the smog problem. When Jed offers to give his millions to President Nixon for the cause, Mr. Drysdale resorts to some outrageous schemes to keep the money in his bank.