The man in the brown suit, by Agatha Christie

 

Agatha Christie's fourth mystery doesn't include any of her more famous detectives. The main character, Anne, is a young woman who loves adventure and decides to solve the mystery of who killed another young woman in an unoccupied home up for rent. The clues lead her to book passage on a ship to South Africa and introduce her to a cast of characters that may or may not be involved in the crime. Stolen diamonds, refugees from justice, secret service investigators, wealthy politicians, and more are all under suspicion, and Anne proceeds to follow the trail to find the murderer and thief. Another of the characters, Colonel Race, appears in three later books by Christie, including two in which he is a close friend of Poirot's. Initially given mixed reviews, The man in the brown suit is just as compelling and page-turning as any Christie mystery. However, the prejudices of the time (1924) are reflected in the depictions of Black South Africans, which may be off-putting to readers.