Doug and his friends are all building soapbox racers for the Mt. St. Buster Downhill Speed Race, and they all want to win, and Doug and Skeeter are having trouble keeping their racer a secret. But once the race starts, there's a disaster on the track, and everyone finds out that helping a friend is more important than winning. Theda and Phil go to Judy's school dance as chaperons and Doug plans a night in the house all by himself. But a huge thunderstorm knocks out the electricity and ruins his plan. In order to get the power back in his house, Doug must find the power box in his basement, in the dark.