在这部红粉煞星喜剧/悬疑片中,贝蒂露（佩内洛普·安·米勒 Penelope Ann Miller 饰）和丈夫艾利克斯（艾瑞克·泰尔 Eric Thal 饰）的感情十分恩爱，最近，她正在着手准备两人的结婚周年纪念日。艾利克斯是一名警探，工作非常的繁忙，纪念日当天，小镇上发生了一起命案，艾利克斯不得不留在犯罪现场进行勘察。
无所事事的贝蒂露带着小狗出门遛弯，路过犯罪现场，小狗嗅到了凶手的气息。之后，在河边，小狗发现了凶手丢弃的枪支，贝蒂露将枪收了起来准备交给丈夫。哪知道半路中，贝蒂露遇见了讨人厌的姐姐，姐姐的喋喋不休让贝蒂露厌烦至极，在洗手间里，贝蒂露掏出枪，却意外的发射出去一枚子弹引来了警察，一时间，人赃俱获的贝蒂露成为了案件的最大嫌疑人。
Betty Lou is a librarian in a very small town. Her husband, Alex, is a police detective who takes her for granted. She is the ultimate mouse. After a gangland figure is mysteriously murdered in town, she finds the murder weapon, but can't get anyone's attention to tell them (we're talking very mousy, here). Finally in a fit of frustration she fires it in a restroom and when taken to the police station insists she is the murderer. It has the desired effect, people do pay attention to her. With hints at social graces from the hookers in her cell block, she's on her way.
