The homework hound is on attack and whatever Tracey and everyone else do, they always get attacked by the hound. Then, the next day, their homework would be piled up in front of the school gate. She had to find out about that hound. While she was completing her invention with Shamus, Megan, her little pesky sister, wants to know how that thing works. Tracey and Shamus made up something that would scare her away. But instead it made her curious. So, Megan wants something to be invisible, Tracey is going to make her invisible. But she couldn't really make her invisible. While Megan was in the stage of being invisible, she also found out that the homework hound, was really Claw, Jim and Jake's dog.