The Monkees are rehearsing a new tune as someone knocks on the door. David answers it and is greeted by Mr. Friar, an innkeeper of The Kibee Estate back in England where David was a stable boy. He informs David that he has to immediately return to England for the reading of the will of the recently deceased Young Lord Malcolm Kibee since David may have been willed the Kibee Estate. When David keeps refusing, Mr. Friar, who has a habit of fainting, repeatedly faints until David acquiesces.
Soon David and Friar fly to England first class, while Micky, Michael and Peter, lacking air fare, are smuggled in mummycases. At English customs, David shows the customs man the three mummy cases with the guys disguised as mummies and recognizes the customs man as Jack Williams, The Monkees TV show's property man, to which the latter replies, "Look, sweetie, I may be Jack Williams The Property Man to you, but to 20 million teenagers, I'm The Customs Man." Then, with a surprisingly convincing impression of Dean Martin, Jack belts out a fine rendition of his closing theme, "Ev'rybody Wants Somebody Sometime," which has him mobbed by a screaming Micky! David and Mr. Friar depart for the estate, leaving behind the mummy cases, where they're greeted by the nearsighted old butler who mistakenly shakes hands with a twig and mistakes Mr. Friar as David's dog. Once inside, David and Mr. Friar are greeted by Young Lord Kibee's nephew, Lance Kibee The Sot, a chronic drunkard who indulges in martinis and Sir Twiggly Toppin Middle Bottom, the executor of the will. The will leaves Kibee Manor to David on condition he lives there for 5 years; if he doesn't, the villagers must buy it for £50,000 otherwise Lance Kibee will inherit the estate with plans to sell it to a land developer. Then David's luggage, the three mummy cases arrive; after letting his mates out, The Monkees are then introduced, by Mr. Friar, to his daughter, Mary, who sees the foursome as "a sister act!". In the car, Twiggly encourages Lance to sell the estate since he envisions a huge commission on the sale as the young inebriated aristocrat continues serving himself liquor hidden in unusual contrivances in the car including inside the wheel horn and in the radio. Meanwhile, the nearsighted butler mistakenly grabs the arm of armor and tells everyone to follow him and soon they all do so, literally in a Three Stooges-type style.
Up in their room, Michael, David, Micky and Peter are bored to the teeth, and when they question Mary Friar what the young people do in town, she reports that moving to the big city and finding lawn moles in the form of dragons furnish all the excitement. Then Twiggly presents the contract (which, like the will, stipulates they must remain for 5 years!) and tries persuading David to leave the estate to the villagers if he's bored there, but Mary reminds him that the villagers don't have the amount of money to buy the estate and they will lose their homes, prompting Mr. Friar to faint once again at the doorway. Later, the guys try to devise a plan or be stuck there for 5 years, but want to leave with a clear conscience. Since they can't simply talk Lance Kibee out of selling the estate, they decide to hold a medieval fair to raise the proper funds on financing the manor's safety. At the ensuing Ye Olde Fair, they only raise £200 at first, but Mr. Friar is sure they'll win the rest betting on the winner in a grand tournament of 2 out of 3 contests: jousting, dueling, and mace and chain. Since David is the lord to the manor, and the one on whom the fate of Kibbee Manor lies, he is the one of the main contestants in the tournament (Twiggly being the other); told this fact, he faints dead away.
Mr. Friar confronts Twiggly about making a wager on the championship and he agrees claiming to be an expert jousting champion, to which Mr. Friar once again faints while the near-sighted butler mistakes one of Twiggly's female companions as Twiggly. At the first contest, Twiggly who is the opponent grabs 2 lances and gives David, who is dressed in a knight's suit, a choice of weapons for the jousting match, and David chooses the drunken Lance Kibee! As Twiggy starts poking Lance with the weapons, he commands him to stop or lose his commission if he's killed, and so David is declared the winner by a pun. But in the next contest which is a fencing duel, David wears a boxer's outfit and boxing gloves, and loses the match prompting booing and hissing from the angry crowd. As Sir Twiggly challenges David to a third duel with mace and chain, a very Old Man, who is the butler's father intervenes and declares the choice of the contests relies upon the people present at the fair. The crowd then decides on a singing contest instead.
At the singing contest, Sir Twiggly, an inexperienced singer, sings painfully off key the traditional Old English ballad "Greensleeves" to a booing crowd. Next it's David's turn who sings it beautifully to the pleased crowd and he's declared the winner. But they learn they are still £40,000 short, thus sealing Kibbe Manor's fate of Lance Kibee as its new lord; Mr. Friar and the Butler insists that David and his mates return to America, aware that he doesn't want to remain there for 5 years. An outraged Mary Friar then gives Lance a piece of her mind as she insults and degrades him, but Lance Kibee declares his love for her and vice versa, and soon the two embrace in a passionate kiss. Then Lance decides to cancel the sale of the estate and remain there with Mary as his bride-to-be and everyone rejoices, all but Sir Twiggly, who faints dead away upon losing his huge commission. Back in America and The Monkees' ramshackle beach pad, Michael ends the show by addressing the audience and is interrupted by Peter who gives a belated Christmas message, and The Monkees give a rendition of "Star Collector."