Ellen Carter's career is on the rocks. She hasn't written a worthy novel since her husband went missing and she was suspected by the police of murdering him. To top it all off, she has reason to believe that her new tenant Leslie Steckler is the serial killer responsible for a number of deaths in the region. But what she doesn't know is that, in the meantime, Steckler has discovered a little secret about her...

科学家韦恩·斯萨林斯基（里克·莫拉尼斯 Rick Moranis饰）发明了能将物体放大缩小的机器，光顾着高兴的他却忘记了告诉他的两个孩子。于是这个神奇的仪器把他的孩子们跟邻居家的两个孩子都给缩小了。