Agatha Christie 
The Man in the Brown Suit 

Agatha Christie, a British author, wrote a detective novel titled The Man in the Brown Suit. When an experience presents itself, Anne Beddingfeld is prepared to experience adventures that come her way. She picks up a piece of paper that was left nearby after witnessing a guy die in a tube station. Later chapters are set in Bulawayo, a fictitious island in the Zambezi, and Cape Town.At the Hyde Park Corner tube stop, Anne Beddingfeld witnesses an accident. After discovering that the "Kilmorden Castle" is a sailing ship, she arranges passage. Suzanne Blair, Colonel Race, Sir Eustace Pedler, Guy Pagett, and Harry Rayburn are introduced to Anne.Anne and Suzanne look through the piece of paper she picked up in the subway. The film roll that Anne discovered at Mill House reminds her of a film container that was thrown into Suzanne's cabin and contained uncut diamonds. According to their conjecture, Harry Rayburn is the man in the brown suit.After being duped by Sir Eustace Pedler, Anne encounters Harry Rayburn on an island in the Zambezi. To ensure that neither is taken advantage of again, they trade codes to be used in subsequent communications. Instead, Anne runs into Chichester, posing as Miss Pettigrew.