Haughty, recently-widowed Margery Heywood and her cleaner Gladys Gladwell go on the run after mistakenly believing that they have killed a teenage burglar, holding up a post office for Gladys' money, and giving petty crook Terry Mason a lift, they are pursued by the police. Their uneasy alliance is made uneasier when Margery learns that her late husband Eric had a 20-year affair with Gladys and the discovery profoundly affect Margery's son Graham. A further shocking revelation takes the pair to Blackpool where another truth is revealed, leading to a genuine friendship and an end to their troubles.