The novelisation was undertaken by the Australian writer and classical music critic Charles Osborne, with the endorsement of the Christie estate.

Agatha Christie began writing Black Coffee in 1929, feeling disappointed with the portrayal of Hercule Poirot in the previous year's play Alibi, and being equally dissatisfied with the motion-picture adaptations of her short story The Coming of Mr. Quin and her novel The Secret Adversary as The Passing of Mr. Quin and Die Abenteurer GmbH.

[1] According to the foreword to the current HarperCollins edition of Black Coffee in its novelised form, she finished writing the play in late 1929.

She mentions Black Coffee in her 1977 life story, Autobiography, describing it as "a conventional spy thriller ... full of cliches, it was, I think, not at all bad".

However, no record exists of such a staging and she was undoubtedly confusing it with the true opening production at the Embassy Theatre in Swiss Cottage (now London's Central School of Speech and Drama) on 8 December 1930.

Wolfit would become renowned in England as an actor-manager, best remembered for his vivid interpretations of Shakespearean roles and other big-scale classical parts.

Lucia implores Poirot to investigate, but Richard reminds her that his father commented on the bitter taste of the coffee she had served him.

Poirot finds a duplicate key to the safe and some letters written to Sir Claud telling him to stay away from "the child of Selma Goetz."

Always it is saved by Hercule Poirot, the great French [sic] detective, who theorizes with the gusto of a man for whom the visible world hardly exists.

Mr Boxer Watsonizes pleasantly, and Miss Joyce Bland, as a young lady who must wait until the very end before knowing a moment's happiness, contrives to excite our sympathy for her distress.

The reviewer stated that, "Miss Christie knows the ropes, keeps to the track, sets her Herculean protector in defence of innocence, and unmasks the real villain at eleven o’clock.

The reviewer praised others in the cast by name and concluded, "the company conduct themselves with a proper sense of the ceremonial involved in a detective play.

But it is surely permissible to be surprised that adult people can be found in fairly large numbers to sit undismayed through the execution of such ritual as this.

"[9] Two days later, Ivor Brown reviewed this second production in The Observer when he said that, "If you are one of those playgoers who are eternally excited by a corpse in the library and cross-examination of the family, all is well.

This time it said that, "Its false scents are made for the triumph of the omniscient Belgian detective, complete according to the best tradition with unintelligent foil; and if they appear sometimes to be manufactured with a little too much determination and to be revived when they seem most likely to be dissipated, they may be allowed because they just succeed in maintaining our sympathy with distressed beauty and our interest in the solution of a problem.

Source:[12] The play was adapted into a motion picture, also entitled Black Coffee, in 1931, with Austin Trevor in the role of Poirot.

Running to 78 minutes, the motion picture was produced by Julius S. Hagan and released on 19 August 1931 by Twickenham Film Studios.