Mr Cope is described as a "pleasant middle-aged American of a strictly conventional type". He has a "long clean-shaven face" and a "slow, pleasant, somewhat monotonous voice".
While at the Solomon Hotel, Mr Cope suggests that some members of the Boynton family go with him to Petra, while the others stay with Mrs Boynton. However, Mrs Boynton says that she does not think they care to divide up, and the children all express the same opinion.
Mr Cope later tells Dr Gérard about the Boynton family. He says that he is an old friend of Nadine, and he knew her before she was married, when she was working to be a trained nurse. He tells Dr Gérard that after Elmer Boynton's death, Mrs Boynton devoted herself to her children, and prevented them from making outside contacts.
Mr Cope also tells Dr Gérard that "a man has got the control of his own destiny right there in his own hands", and that a man should strike out and make something of his life. He believes that if Lennox does not appreciate Nadine as she ought to be appreciated, she should leave him.
According to Dr Gérard, Mr Cope has "a nice, upright, sentimental, normal American mind", and so he believes in good rather than evil. He sees that something is wrong with the Boynton family, but believes that it is misguided devotion on Mrs Boynton's part, and not active maleficence.
Mr Cope tells Dr Gérard about a servant he heard about, who had been employed by Mrs Boynton. The girl was pregnant, and Mrs Boynton was kind to her, only to turn her out of the house a few weeks before the child was born. Mr Cope says that he cannot understand it, and is shocked when Dr Gérard suggests that this incident gave Mrs Boynton a lot of enjoyment.
On the day of the murder, Mr Cope goes for a walk with members of the Boynton family, as well as Sarah and Dr Gérard. On his way back to the camp, he met Lady Westholme and Miss Pierce.
It is later revealed that Nadine had planned to leave Lennox for Mr Cope. However, after the death of Mrs Boynton, Nadine tells him that she cannot leave Lennox. He tells her that all he ever wanted was for her to be happy, and that she and Lennox will now be able to live a life of their own.
Mr Cope later marries Carol Boynton. At the end of the novel, he and Carol, with the other members of the Boynton family, have supper at the Savoy.
Appointment with Death (1988 film)
In the 1988 film adaption of Appointment with Death, Cope is portrayed by David Soul. Here he has a larger role than in the book. He is the family lawyer of the Boyntons and is involved in other sideplots. At the beginning of the show, he informs Mrs Boynton that her husband Elmer Boynton had made a new will a few days before he died which divided the fortune between her and the children as opposed to leaving everything to her. Mrs Boynton tells Cope that she knows about his "share pushing" involving the Bolivian Silver Mining Corporation and intimidates him into burning the new will.
Subsequently, Cope trails the Boynton family in their tour of Europe, meeting up with them at Trieste. Unique to this adaptation, he is having an active affair with Nadine (in the original this is dormant until much later). Like in the original, Cope is an old flame of hers. They meet in Trieste and he gives her a cigarette case with an inscription as a gift.
Later, on board the ship to Jaffa, Mrs Boynton realises that Cope is a threat because he can talk about the new will and the fact that they had burnt it. During dinner, she tries to serve him a poisoned drink. This attempt fails because Lennox Boynton discovers the cigarette case and punches Cope on the face, causing him to spill his drink.
On arrival at Jaffa, he notices Miss Quinton and begins to take an interest in her. For the rest of the plot, his attention is divided between Miss Quinton and Nadine. He breaks off from the Boynton party to join Miss Quinton at Qumran. They were later reported as missing, although all they had done was take an excursion to the next valley and spend a night in a Bedouin camp.
When the Boynton family arrives at Qumran, Cope does join the Boynton children on a walk. Here, as in the original, he tries to persuade Nadine to leave Lennox to join him. However, Nadine later tells Poirot she was doing this just to stir Lennox into standing up for himself.
Unique to this adaptation, Cope pairs off with Miss Quinton at the end and not Carol Boynton.