When Cindy's doll, Kitty Karry-All turns up missing, she accuses Bobby. This leads to a mock trial with Alice as the judge to determine Bobby's guilt or innocence. Then later Bobby's kazoo turns up missing and he blames Cindy.

Marcia's sense of security is shattered when Cindy inadvertently gives away her diary to a book collection. Marcia is especially concerned since in it, she confessed a secret desire for Desi Arnaz, Jr.

Tired of being the middle blond girl of the family, Jan tries to alter her appearance by buying a black wig, which she intends to wear to a friend's upcoming birthday party.

Tired of being in Marcia's shadow, Jan is determined to do something that Marcia never did. However, Jan becomes more depressed when she fails to make the pom-pom team and her friend makes the squad. Then she wins first prize in the essay contest and finds out her teacher made a mistake in scoring.

Marcia makes a promise that she will get Davy Jones to perform at the prom. A promise she quickly learns is going to be very difficult to keep, since trying to get a hold of him is almost impossible.

Feeling immature because she is the youngest, Cindy feels that she isn't appreciated until she gets a mysterious letter from a secret admirer.

Jan is fed up with the number of people in the household and voices her want to be an only child. So the other kids oblige and give her all the space she wants and she finds that she has more space than she needs or even wants when she begins to excluded from the other kids activities.

Marcia has a big problem when she inadvertently makes two dates for the same night. One with Charlie and the other with Doug, the big man on campus. She makes a excuse to Charlie to go out with Doug but quickly learns Doug was only interested in having a pretty girl on his arm after Marcia is hit in the face with a football.

Peter's new detective kit comes in handy when Cindy touches and then looses a pair of antique earrings that Marcia was borrowing from Carol that she warned her not to touch. This leads Peter and Cindy on an all out search for the missing earrings.

After Bobby defends Millicent at school she rewards him with a kiss and he immediately sees sky rockets. This leads him to try to kiss her again but after seeing those sky rockets again, she delivers the news that she may have the mumps.

Jan becomes convinced she is a "no talent loser" after she fails to make it into a ballet recital which follows with her totally dropping out of ballet and on to tap dancing which totally drives the Brady family crazy.

Mike has to present some plans for an addition at King's Island, an amusement park in Cincinnati, so he invites the whole family along but when a mix-up occurs Mike is left with a Yogi Bear poster while Jan is left with Mike's plans which she loses on one of the many rides in the park.

After meeting an astronaut, Bobby and Peter begin wondering about life on other planets. Their wonder turns to excitement when they claim to have spotted a UFO and camp out in the backyard to get it on film.

Carol breaks the news to Mike that she's expecting and an eavesdropping Bobby and Cindy assume that she's pregnant and pass it along to the rest of the family. Unknown to them what she meant was that she's expecting her nephew, Oliver to move in with them over the summer while his parents are in Africa.