Mike takes the entire family on a trip to King's Island amusement park, where he is to submit plans to a client, but the a mix-up causes the blueprints to go missing at the park.
Mike has a big surprise for the family. His boss, Mr. Phillips, has approved the King's Island amusement park plans he has been working on and wants him to go to Cincinnati to present them. In turn, Mike can bring along the family to spend time at King's Island. They are all excited by the news. Once there, Mike is dismayed to learn that he only has a truncated thirty minute meeting to present the plans before the amusement park's directors, Mssrs. Remington and Dempsey, head off on another business trip. Regardless, Mike vows to have a good time seeing as much of the park with the family before his meeting at one o'clock in the afternoon. The morning adventures include Greg trying to find a girl he just met and likes named Marge, who works at the park dressed as an animal, but Greg doesn't know which one. And Bobby and Cindy try to justify eating a lot of junk food before their scheduled meeting with the family for lunch. At lunch, Jan asks her father if she can use one of his two canisters, which currently hold the amusement park plans, to put in a poster she just purchased. As Mike puts all the drawings in one canister, he gives the other to Jan. Unfortunately for Mike, he takes Jan's canister to the meeting, while Jan takes his. By the time he finds out the error at the meeting, he has only thirty minutes to find Jan and return to the meeting with the drawings. With ten minutes left, Mike finally finds Jan, who he learns lost the other canister. It's a ten minute race as everyone in the family scours the park to find the lost canister.
The Bradys visit King's Island Amusement Park, where Jan accidentally mislays her father's plans. The family frantically searches the park in a race against time to salvage a potential deal between Mike's firm and the amusement park's board of directors.
- This episode opens with the whole family at home anxiously waiting for Mike (Robert Reed), who has called ahead to tell them he has a surprise or all of them. When he walks in, he informs the Bunch that he is going to Cincinnati, Ohio. They are, understandably, NOT excited until he adds that he is delivering plans for a big amusement park (which just happens to be Kings Island) and he thought they all might like to go with him. When they arrive, Mike finds out that he is only going to have about half an hour at 1:00pm to meet with the principals before they catch a plane to New York. He remarks to Carol (Florence Henderson) how this trip reminds him of their honeymoon, having the six kids along. The next scene opens with all of them at the main entrance to the park. Mike and Carol tell the kids that they can go do whatever they like but they will all meet for lunch. Carol admonishes Bobby (Mike Lookinland) and Cindy (Susan Olsen) "not to fill up on a bunch of junk food". There are then scenes along the way of all of them riding different rides and, of course, Bobby and Cindy eating first apples, then ice cream, then popcorn, etc. Greg (Barry Williams), of course, meets a girl, Marge (Hilary Thompson), working at one of the games and spends most of the episode following her around and trying to get a date with her. Marcia (Maureen McCormick) and Jan (Eve Plumb) are then seen exiting one of the shops where Jan has purchased a Yogi Bear poster for one of the kids she babysits for. When the group meets for lunch, Jan puts the poster on the ground where it ends up under Peter's (Christopher Knight) feet. Jan asks Mike if she can have one of the canister tubes he has the plans in to keep her poster in. Mike explains that those plans are the whole reason for their being on this trip. Jan then explains how important it is that she keep this poster nice and "she has to get it all the way home". Mike consolidates his plans into one canister and puts the Yogi poster in the other and sets both of them down by his feet. After lunch Mike is shown at his meeting where he starts to show the clients his plans only to find out that he has a Yogi Bear poster in his canister. The clients remark about "the joke" but want to see the plans as they are in a hurry. Mike explains that "the joke" is unintended and his daughter must have his plans. Mike tells them he is sure he can find Jan and get the plans back. The clients then explain that they will be leaving for their flight in half an hour. The next few scenes show Marcia and Jan going from one ride to another. As they are getting off one of the rides, Jan remarks about going back to the poster shop to exchange her poster and she realizes she has lost the canister. The next scene is with Greg in a bear costume trying to find Marge. As he finds her and, is again trying to get a date, Mike walks up and asks her if she has seen Greg. Greg takes off the bear head and Mike tells him he needs to find Jan and his plans. The rest of the group, minus Marcia and Jan, are then gathered and Mike tells them to spread out and find Jan so he can get his plans. When they find her, he tells them, they should get the plans to the manager's office right away. Carol, Mike and Alice (Ann B. Davis) are then seen running into Marcia and Jan outside the poster shop. Mike asks Jan what happened to his plans and explains about the switch. She explains that she lost them and he tells the group they have to find them. They all search the park high and low looking for the canister. Just as Marcia and Jan are getting ready to get on a boat to go over to an island they were on earlier, Jan finds the canister lying in the bottom of the boat. Marcia and Jan take off running across the park with the plans. They run until they run into Alice who takes over and runs until she finds Cindy and Bobby. Bobby and Cindy take off running until they find Greg and Peter who run until they find Carol. As they hand the plans off to Carol she remarks that she "hope it isn't too late". The next scene is of Mike and his clients leaving the manager's office. As Mike explains to them that he can get duplicates from his office, they tell him that would be too late as they will be making a decision in the morning. Carol runs up with the plans in hand just in nick of time. The family then goes and has another ride on the roller coaster. The final scene shows Mike and Carol back in their room the next morning. The phone rings and it is Mr. Phillips, Mike's boss, letting him know that the clients chose his plans. A bear walks in and they assume it is Greg, only to find out that it is Peter. Peter explains that Marge was supposed to be fill in for her brother, being the bear, and Greg gave him $5 to do it so he could have lunch with Marge.