Bank teller Lee Remick is accosted in her garage one dark night by asthmatic psycho Ross Martin. He forces her to go through with an elaborate robbery scheme, threatening to kill Lee's teen-aged sister Stefanie Powers if the police are summoned. FBI agent Glenn Ford suspects that something is amiss and advises Lee to play along with Martin, hoping in this way to capture this dangerous criminal with a minimum of bloodshed. Unfortunately, Martin is as clever as he is deadly, always managing to stay one step ahead of Ford. The now-famous climax of finds the feds closing in on Martin during a crowded night baseball game at San Francisco's Candlestick Park. is based on the Gordons' novel .