After weighing herself, Serena thinks she's gaining weight and is getting fat. Luna draws a picture of "Sailor Blimp," so Serena gets upset and looks into this weight thing. At school, Melvin shows Serena some pictures of Mrs. Haruna, who lost tons of weight at a new fitness center. Serena, Molly, and their friends decide to check this place out. The fitness instructor, Jed, is a "total hunkster," so the girls do exactly what he says. Luna investigates and notices that their are 'relaxation pods' in the basement that drain human energy, and Mrs. Haruna's going to die soon from it! She pulls Serena away from her dieting to check it out. It's apparent that this whole fitness center is another trick by the Negaverse to steal energy! Serena transforms and battles hypnotized body builders, one of her toughest challenges yet (the first and last time you'll see her actually hit someone). The day is saved, by Sailor Moon!