A Personal Affair is a drama that captures the story of Barbara Vining (Glynis Johns), a teenager who finds herself entangled in a mess of gossip and lust. Barbara becomes infatuated with one of her teachers, Stephen Barlow (Leo Genn). When Barbara starts to take things a little far, Barlow's wife Kay (Gene Tierny), becomes upset and decides to meet with Barbara to discuss her feelings. Everything goes okay, until the day that Barbara ends up missing. The community has now shifted their focus to the Barlows. Police suggest that her disappearance is either a suicide, but the more likely scenario, according to them, is that foul play was involved. Kay is now panic-stricken, as all eyes are turned to her and her husband. If the police are not able to solve this case, then they will have to do their best to convince the courts of their innocence, which will not be an easy task for the duo.