This is Christie’s fourth novel published in 1924. She did write many short stories in the year or so before this book. It is interesting that she first published in 1920 (The Mysterious Affair at Styles) but nothing in1921 or 1943. Otherwise, she had at least one book published every year until her death, and usually more than one. Her second novel, in 1922, was The Secret Advesary featuring Tommy and Tuppence. While she did write three more Tommy and Tuppence novels, most people today are unaware of them. It is telling that her first and third novels featured Poirot. He appeared 35 times in novels and in 49 short stories. Miss Marple appeared in only a dozen novels and 20 short stories.
A young woman named Anne Beddingfield witnessed a man falling to his death on the Underground tracks. She watched as a man claiming to be a doctor examined him and declared him dead. For reasons she could not know, she followed the man in the brown suit an picked up a piece of paper he dropped. That was the beginning of an adventure that took her to South Africa.
Anne tells most of the story with a few snippets from the diary of Sir Eustace, who also sailed to South Africa, filling in some details. They all disembarked from the ship and traveled by train to Jo-berg and became caught up in the very real Rand Rebellion (1922).
This story is more like Tommy and Tuppence. Anne discovers evidence by sticking her nose where it does not belong and getting pinched more than once, but she does uncover clues.
Christie is always a good read, even if it is not her best work. Besides, it is now a period piece.