After having several planned robberies ruined by the unexpected arrival of the pompous but well-meaning local Bishop Tweeney, the Clarkson Gang, a quartet of inept small time thieves, risk taking a convent full of nuns as hostages for ransom to get cash for themselves and to solve an elderly friend's problem while a legislative blooper has temporarily left the state without a law against kidnapping. The gang expect to have problems with the diocesan bureaucracy but quickly find that their more immediate and on-going challenge is the war of wills with the local superior, Mother Thelma, who refuses them and confuses them by also being their ally at times as she eventually learns their full motivation. The angry mob of protestors that gather at the edge of the large convent property develop their own collective intention - to block delivery of any ransom payment and to lynch the four. The mob are one of the many surprises the gang must deal with to survive and profit from this. Mother Thelma works hard to keep the would-be rescuers away from the convent to let things play out without violence but once it is dark and fire alarms sound in the building things get totally chaotic.