Haughty, recently widowed Margery Heywood and her cleaner Gladys Gladwell go on the run after mistakenly believing that they have killed a teen-age burglar and, having held up a post office for Gladys's money and given petty crook Terry Mason a lift they are soon pursued by the police. Their uneasy alliance is not helped when Margery learns that her late husband Eric had had a twenty year affair with Gladys, the discovery of which had profoundly affected 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.