The Brady bunch are out at the grocery store. They notice that a hip man has been following them all over the store and is making his hands to make filming motions at them. He approaches them and says they "are it". He is Skip Farnum, a TV director from Farnum Film Enterprises, a commercial-making company. Skip wants the Brady bunch to do a commercial on Safe, a laundry soap powder.
The kids are all excited and rush to the phone to tell all their friends the news when they get home. Skip arrives to scan the Brady house for the commercial, which he finds groovy, while the Brady parents examine the contract. Meanwhile, the kids dream up ideas on what they could spend the money on, and doing more commercials. Mike cannot make sense of the contract and decides to get legal advice.
Then Carol raises a really serious problem - they do not use Safe. They use Best because "best is best", and better than the Safe that Carol tried. Mike believes that there is a principle here, and they cannot in all honesty do the commercial. He has to cancel the commercial with Skip. The kids are crushed.
Then Mike phones to tell Carol that Skip said the Safe she had used was the old one. The one for the commercial is a new improved formula. The Bradys decide to do their own test: Safe vs Best. If Safe wins, they will do the commercial. The kids have enormous fun deliberately dirtying their clothes for the test. However, Alice cannot remember which powder cleaned which test pile. A re-test is done, and Safe is declared the winner. The Bradys are free to do the commercial, and the contract is all signed.
Skip gives the Bradys scripts but does not want rehearsals so as to keep things natural. The Bradys are told to just learn their lines. However, the Bradys get nervous about looking stupid. They decide to get acting lessons from one Myrna Carter. Mryna's coaching has the Bradys going ridiculously over the top in melodramatic, idiotic and misguided efforts to show how "motivated" they are about Safe and appearing "bigger than life." Skip is appalled and calls the shooting off. He chose the Bradys because they looked a nice, natural American family, but now they are "a bunch of ding-a-lings." As Skip leaves, he says the Bradys' conduct reminds him of a horrible actress he worked with - Myrna Carter.
However, under the terms of the contract Skip must honor his payment to the Bradys, and he does. Carol is horrified to discover it is 2000 boxes of Safe arriving on her doorstep.