|“||I’ve never forgotten anything – not an action, not a name, not a face.||„|
|~ Lady Boynton's famous threat towards Lady Westholme (which was thought to be a threat towards Sarah King)|
|“||You do see, don't you, that she's got to be killed?||„|
|~ Raymond Boynton to his sister, Carol, about planning their mother's murder|
Lady Emily Boyton (aka Mrs. Boynton) is the secondary antagonist of Agatha Christie's Appointment With Death, and the book's primary victim. She is also the posthumous main antagonist in the novel's stage play adaptation and its 2008 television film adaptation in Agatha Christie's Poirot.
Lady Boynton is the sadistic and condescending matron of Boynton family, as well as the abusive mother of her four children. In Agatha Christie's Poirot, she was renamed as Leonora Boynton.
In the 1988 film adaptation, she was portrayed by Piper Laurie, who also portrayed Margaret White in the 1976 film adaptation of Carrie. In Agatha Christie's Poirot, she was portrayed by Cheryl Campbell.
|“||Goodbye, Mrs. Boynton. I hope you'll have a nice trip. You've wanted to be very rude to me. You've tried to prevent your son and daughter making friends with me. Don't you think, really, that that is all very silly and childish? You like to make yourself out a kind of ogre, but really, you know, you're just pathetic and rather ludicrous. If I were you I'd give up all this silly play-acting. I expect you'll hate me for saying this, but I mean it-and some of it may stick. You know you could have a lot of fun still. It's really much better to be friendly and kind. You could be if you tried.||„|
|~ Sarah King's commet towards Lady Boynton and her death|
Formerly a prison warden, Lady Emily Boynton is the second wife of the late Lord Boynton and stepmother to the three Boynton children – Lennox, Raymond, and Carol – and mother to Ginevra. She carried over her sadistic and domineering attitude from her original occupation onto her children, being sadistically abusive.
After her husband's demise, she blackmailed the family lawyer, Jefferson Cope, into destroying a second will of her late husband that would have freed the children from her dominating influence and allowed them to inherit $200,000 each.
Sarah King, who was fell in love with Lennox Boynton, attempted to save the Boynton children from their harm, but when she tried to confront Lady Boyton, Sarah heard her saying she never forgot anything, something she thought to be herself. However, it was revealed to be Lady Westholme, a parliament member and Lady Boynton's secretary, who would become a new subject to torture due to Lady Boynton's lust for torment.
Lady Westholme later poisoned Lady Boynton, using a lethal dose of digitalis under the guise of an inconspicuous Arab servant to commit the murder, as an attempt for keeping her past secret as a criminal, once imprisoned in the very same prison where Lady Boynton served as its warden. After Poirot solved the case, Lady Westholme committed suicide to evade capture. The Boynton children were eventually freed from their abusive mother and moved on to their newer and better life.
- The famous threat made by Lady Boynton was ommitted in Agatha Christie's Poirot, due to the adaptational change of Lady Westholme's murder motive in the series adaptation, and thus the line became irrevalant.
- In the Agatha Christie's Poirot, Lady Boynton was not a retired warden. Instead. she was in control of a large financial empire. She could not have any children of her own, so she selected her children from orphanages, all of whom were badly abused and tormented.
- In the stage play adaptation, the reason behind Lady Boynton's death changed drastically. Rather than being murdered by Lady Westholme, Lady Boynton commits suicide in order to instill fear and paranoia over her children, intending to make her iron grip on their lives last even in death.