Fanny Pye's London house, bought for a song many years earlier, is now worth half a million. When she intervenes in a stret brawl and is hospitalised, her children tactifully suggest that she move to the suburbs, coincidently releasing some useful 'family money'. Fanny has different views about inheritance and property is anyway more concerned that she cannot properly remember the events of that night and the death of a stranger. Then, as her amnesia clears, she is overwhelmed bu a terrible sense of danger.