Nanny (Bettie Davis) has been with the Fane family for many years.She cared for Virginia (Wendy Craig) and her sister, Penny (Jill Bennett), before looking after Virginia's children. Susy (Angharad Aubrey) and Joey (William Dix).When Susy drowns in the bath, Joey is blamed for her death. Virginia suffers a breakdown and Joey is sent to a special school where he is analysed by psychologists. Shunned by her exasperated husband, the grief-stricken Virginia needs Nanny more than ever.Unfortunately Joey's stay in the institution has done little to mellow him. When he returns he insists that he was not involved in Susy's death, and maintains that his sister was actually murdered by the evil Nanny. After a further 'accident' in the house. Penny arrives to look after th obnoxious Joey. Soon, however, Penny begins to suspect that the boy may have been telling the truth all along...The result of a sometimes uneasy collaboration between the legendary Bette Davis and two of Hammer's greatest talents. Writer Jimmy Sangster and director Seth Holt.