Susie attacks Stewie; upset by this, Peter takes Stewie to train at the local gym. A trainer notices Stewie struggling with barbells and offers them steroids. Peter injects the drugs into Stewie, who becomes well-developed. As time passes, Stewie’s drugs gradually wear off; to his horror, his skin becomes loose and flabby. He jumps out his bedroom window to avoid Brian (whom he had previously annoyed), only to have his loosened skin help him glide to safety. At the end of the episode, his body inexplicably returns to normal.