On her way back home following an illicit encounter with her lover, Mary is breathalysed after having a minor road accident. As an alternative to court proceedings and a possible prison sentence, she is offered a physical punishment with cane and strap. This brings her into contact with Alison Fraser, a government-appointed corporal punishment officer whose job involves administering discipline to a wide variety of clients. Efficient and professional, Alison disciplines Mary with strap and cane on her bare bottom over a period of six weeks.

In her private life, Alison is a lesbian - a fact known only by a couple of her close friends. One evening at a club, she is introduced to a young woman named Karen, who has recently broken up with her boyfriend, and the two women strike up a friendship. It is a friendship that is platonic at first, and gradually changes. Karen is fascinated with spanking, and when she finds out what Alison does for a living, begs her to spank her. Alison agrees, and afterwards as she is rubbing cream onto Karen's bottom, the two women end up having a sexual encounter. The sex and spanking sessions continue, and the two of them take a holiday in Scotland ... with an unexpected outcome.