What to read after A Fiction Story the Mysterious Affair at Styles by Agatha Christie?

The novel is set in England during World War I at Styles Court, an Essex country manor (also the setting of Curtain, Poirot's last case). Upon her husband's death, the wealthy widow, Emily Cavendish, inherited a life estate in Styles as well as the outright inheritance of the larger part of the late Mr. Cavendish's income. Mrs. Cavendish became Mrs. Inglethorp upon her recent remarriage to a much younger man, Alfred Inglethorp. Emily's two stepsons, John and Lawrence Cavendish, as well as John's wife Mary and several other people, also live at Styles.