A shrunken Shaggy, Scooby, and Scrappy each wear springs in an effort to get to the shrink ray. Scooby is captured by the evil scientist and loses his spring in the process. When Shag and Scrappy bounce into action to rescue him, the next shot has Scooby wearing the same spring he previously lost.
The evil scientist enlarges the Mystery Machine before the shrunken Shaggy, Scooby, and Scrappy spring into action to stop him. However, after they capture him, they tie him up and drag him on a dolly tied along with the Mystery Machine which is still shrunken even though it was previously restored to normal size.