Tabby is not the most energetic cat. She lives her life between her bowl and her basket and if she ever wants to get on a chair, Polly is always there to lift her up. Life is good, until the day she gets stuck in the cat flap. Dad knows that something must be done about Tabby's flabbiness and Tabby soon finds herself competing with a fitter kitty for food, basket space and Polly's cuddles. So Tabby devises her Secret Feline Fitness Programme to show Fit Kit what's what.