At the beginning of the episode, Heather Locklear walks into the building for her big appearance on the show, fully unaware that all of the Muppets are in the closet hiding from her. At the time, Heather was (and still is) best known for playing the evil Amanda Woodward on Melrose Place, and the Muppets were afraid of her because of all of the bad things her character has done on her show. After finally finding the Muppets, Heather reassures them that she's nothing like her Melrose Place character.
Heather appeared in a sketch written by Miss Piggy's dimwitted nephews, Andy and Randy, playing the antagonist, Queen Hawaya, while dressed in a skimpy Queen Bee outfit. Later in the show, Heather runs into Beaker and eats a chimichanga, unaware that it was one of Bunsen Honeydew's wacky experiments. Bunsen's "Mood Meals" consisted of a chimichanga and biscotti, with biscotti turning a person immensely nice, while a chimichanga turns a person evil. After eating the chimichanga, Heather becomes mean and nasty to Beaker and plants a kiss on him. She later accuses Beaker of coming on to her and punches him; sending him flying past Clifford, and later enters the control room and snarls at the Muppets that "it's going to be a bumpy night." Heather cackled evilly as lightning crashed to cement her villainous turn.
Despite the chaotic turn of events, Clifford decided to cast the evil Heather in a Melrose Place-like sketch as a character named Diamanda, a spoof of Heather's villainous character on the actual show. Unfortunately, Heather appeared in pigtails and pajamas, and with an overly nice persona, which meant she had clearly eaten the experimental biscotti. After the skit, Bunsen and Beaker used hypnosis to control Heather's good and evil sides, with two taps bringing out each one. To test out the experiment, Beaker taps twice, which unleashes the evil Heather, who threatens to shut Bunsen down if she doesn't get a cut in their food experiment. Beaker taps twice again to bring back Heather's nice side, and it gets out of control at the finale skit with Kermit. Part of Kermit's routine included tapping his cane twice, and as he does, Heather switched from good to evil and back several times. A list of things that Evil Heather does during the segment include popping a balloon, tripping random people, and destroying Bobo's hat. Heather is finally brought back to normal when Beaker smacks her on the head with a trout.