The Clampetts head to England to visit the castle Jed inherited. Misunderstandings abound, from Jethro mistaking San Francisco for London, to the impounding of Granny's medical supplies, to the real intentions of the elderly chemist.
The Clampetts finally make it to their new castle and try to adjust to the English way of castle life, at the least the way Jethro thinks it is, based on his understanding of English myths and legends.
Granny wants to leave England until she thinks the feudal system means feuding with the neighboring castle. Once back in America Jethro decides to continue his Robin Hood ways in a local version of Sherwood Forest.
Since Granny can't plant crops in their yard, Jed thinks the solution is to buy her a plot a land somewhere else. He figures a place called Happy Acres is the best spot to buy land, not realizing it's a cemetery.
Jethro thinks he wants to be a naval frogman but Granny is concerned her tonic has transformed him. Mr. Drysdale, concerned about finances, has Miss Jane distract Jethro with comics causing him to want to fly to the moon.
Jethro heads down to the Reserves HQ while wearing an ancestor's Confederate Army uniform. The Sergeant thinks he's an actor there to participate in a Civil War reenactment. Jethro runs home to tell Granny the Civil War is still on.
Granny confuses a movie with a restart of the Civil War, convincing Ellie and Jethro to join the Confederates. Granny wounds the actor playing Grant with Ellie's cookies, taking him to cure him with her "rheumatism" medicine.
Col. Blake asks the actor playing Gen. Grant to play along with Granny so that the Civil War movie can continue. Meanwhile, Jethro uses his 6th grade education to take the written test to enter the Reserves.
Granny competes against Mrs. Drysdale as artists and tells Jed about her uncle the barn painter. Jed and Jethro go to an upscale gallery to buy a painting but are mistaken for gardeners. Bessie the chimp dabbles with a paintbrush.
Jethro decides to turn his favorite thing eating into a job by getting the family involved in buying a diner. The family's choice of offerings lead to a lack of customers so Mr. Drysdale tries to fix things.
Jethro worried that his diner the Hungry Gizzard has no customers, has a wonderful idea. He busts in on Mr. Drysdale trying to impress the wealthy Vanderpools announcing the restaurant is going topless. Confusion insues.
Granny wants to leave sunny California because she misses the winter season sending Mr. Drysdale into a panic. The banker enlists Miss Jane in an elaborate scheme to convince the Clampetts that a blizzard has occurred.
After Mrs. Drysdale complains to Granny they have a physical brawl. It leads to Jethro explaining to Jed and Granny about TV wrestling. While watching Granny thinks its real so she decides to rescue Rebecca, one of the performers.
Granny is worried about Miss Jane's spinster hood and convinces Jethro to ask her to marry him. Granny assures him that she will decline the proposal but Hathaway accepts leading to panic in the Clampett household.
Jethro is on to his next big idea and wants to play the violin. Jed asks Miss Jane to find a teacher and she hires Stromboli, a famed classical virtuoso. But the Clampetts want fiddle music so they find someone else.
Granny is on the warpath concerning the chaos caused by Ellie's critters and declares either they go or she does. Mr. Drysdale is equally irritated by the expense of his wife's poodle. Jed tries to find a solution.
Granny and Jethro believe they have psychic abilities, but Granny's predictions stop coming true. With her reputation on the line, she picks a stock for Mr. Drysdale that could cost him a small fortune.
Mr. Drysdale wants to film a Super Banker commercial with the old Clampett cabin before they became wealthy. The shack's return has his wife unhappy and an accident has Granny preparing a head transplant for Mr. Drysdale.