On Halloween, Johnny finds a creepy room in the basement of the apartment building. The room is inhabited by a mad scientist, Ed, who captures Pete and Ashley and swaps their brains. He then does the same thing with Berg and Sharon. Johnny comes down and rescues them but is unable to swap their brains. The confusion causes considerable difficulty in the relationships. Eventually, Johnny decides to try to use the equipment to put each person's brain back into the right person. He succeeds--with one exception.
—jem