|“||When you've been denied justice... you are incomplete. It feels that God has abandoned you in a stark place. I asked God... I think we all did... what we should do. And He said, "Do what is right." And I thought if I did, it would make me complete again. (Poirot: And are you?) But I did what was right.||„|
|~ Mary Debenham to Poirot (2010)|
|“||Not now. Not now. When it's all over. When it's behind us. Then...||„|
|~ Mary Debenham to Colonel John Arbuthnot, also her most famous quote|
Mary Hermione Debenham is a major protagonist in Agatha Christie's 1934 Hercule Poirot novel, Murder on the Orient Express, and its adaptations. She is one of the twelve culprits of the story that killed Lanfranco Cassetti.
Being one of the closest familiars to the Armstrong Family before its tragedy, Ms. Debenham was a professional governor to Countess Andrenyi and formerly a tutor to the late Daisy Armstrong, and a personal secretary to the late Sonia Armstrong. In the 2010 film, she had her arm broken and paralyzed by Cassetti's thug. She participated his murder and was one of the twelve who stabbed him to death in his sleep.
After the deaths of Daisy, Mary became a governess in Istanbul teaching two children. She was in a relationship with Colonel John Arbuthnot, the closest friend of the late Colonel Armstrong, who also participate the murder to avenge his friends. Their brief interaction whilst pretending as strangers was spotted by Poirot, and it later became a factor to solve Casetti's murder. She was eventually spared alongside other culprits because of the sympathetic circumstances behind the murder.
On board the Orient Express, Mary occupied berth No. 11, sharing a second-class compartment on the Calais coach with Greta Ohlsson who was in the lower berth, No. 10.