The Shadow on the Glass is a short story written by Agatha Christie.
Mr Satterthwaite is a guest for a week at a house party held by Mr and Mrs Unkerton at their home, Greenway's House. The people invited there are an unfortunate mix in that there have been relationships between some of the people there in the past. Mr Richard Scott, there with his new wife Moira, is the best friend of another guest, Major John Porter. Both men are Big-game hunters who made trips in the past to the African interior. Mrs Iris Staverton arrives. She is a bewitching woman who supposedly had a relationship in Africa with Richard Scott. Also present is Lady Cynthia Drage, a gossipy society woman, and the young Captain Jimmy Allenson who is liked by everyone and who Lady Cynthia met in Egypt the previous year where the Scotts also met and married.
To add to the atmosphere at the party, the house is supposed to be haunted by the ghost of a cavalier who was killed by his wife's roundhead lover. The two then fled the house but looking back saw the unmistakable image of a cavalier looking at them from an upstairs window, supposedly some blemish on the glass pane. This has been replaced many times but the mark always returns on the new pane, usually a month or so after it has been installed. This window has now been panelled over and a new window put in the room which is presently occupied by the Scotts. Mr Satterthwaite shows this window to Major Porter from its nearest viewpoint which is within the densely-hedged privy garden. The blemish cannot be clearly seen from there so Satterthwaite takes his companion to a grassy knoll some distance from the house where the image is clearer. On the way, Major Porter confides to Satterthwaite that Mrs Staverton ought not to have come to the party. On the way back, they overhear Richard Scott and Mrs Staverton talking, the lady telling the hunter that he shall be sorry and that jealously can drive a man to murder. Satterthwaite has a premonition of tragedy.
That evening, Mrs Unkerton tells Satterthwaite that she has sent for glazier to replace the haunted pane of glass, determined to be rid of the image once and for all. Satterthwaite does not believe she will be successful but realises that she also senses the tension in the house. The next evening, Satterthwaite and Porter retrace their steps in the dusk to the grassy knoll and see that Mrs Unkerton's plan has not yet been put into place as the cavalier's image is still there. On their way back, they hear two shots from the privy garden and find Mrs Staverton holding a gun and two dead people on the ground – Captain Allenson shot in the chest and Mrs Scott shot in the back. Mrs Staverton insists that she simply reached the two corpses first and picked up the discarded gun. While the police are fetched, Satterthwaite notices a spot of blood on the earlobe of Mrs Scott and sees that one of her earrings has been torn away.
The police arrive and carry out their investigations. The situation looks bad for Mrs Staverton as no one else was seen to enter the privy garden prior to the shots being fired although the lady herself insists that she turned the corner after hearing the shots and found the bodies. In the middle of the enquiry a guest arrives at the house – Mr Quin. Satterthwaite vouches for him and his ability to make people see new angles on problems. Prompted by Quin, Satterthwaite tells of seeing the torn earlobe and it is realised that the earring could not have been torn out as Mrs Scott fell. It must have been shot out which means that she was hit by two bullets and the one that passed through her also killed Captain Allenson, meaning that she must have been close to him at the time, perhaps in his arms. The Scotts met in Cairo the previous winter when Allenson was also there – were Mrs Scott and Allenson lovers?
Further questioning the people there, Unkerton reveals that the glazier did visit that morning, even though Satterthwaite and Porter both saw the image of the cavalier some hours later. Rushing to the haunted room, they find a small feather in the panelling which matches the ostrich feather from one of Mrs Scott's hats. Quin verbally recreates the crime – Richard Scott saw his wife and her lover from the window when he pulled the panel back. Remembering the story of the cavalier, he donned his wife's hat to look like the cavalier's image (in case anyone were watching) and shot the two from his window, then throwing the pistol onto the grass below. He was happy to let Mrs Staverton take the blame as, contrary to popular belief, she fell for Porter in Africa, not Scott. Porter didn't realise this and Quin suggests he go and comfort the wrongly-accused lady.
- Mr Satterthwaite
- Harley Quin
- Mr Unkerton
- Mrs Unkerton
- Mr Richard Scott
- Mrs Moira Scott
- Major John Porter
- Mrs Iris Staverton
- Lady Cynthia Drage
- Captain Jimmy Allenson
The Shadow on the Glass: First published in issue 236 of The Grand Magazine in October 1924.
In 1930 the short story, along with other Mr Quin short stories, was published in the short story collection The Mysterious Mr. Quin.