The Secret of the Ninth Stone

In 1864 London, orphan Sarah O'Reilly disguises herself as a boy to work at a newspaper, where she encounters Lily Korechnya, a wealthy widow writing under a pseudonym. Tasked with cataloguing a magnificent jewel collection for Lady Cynthia Herbert, they become intrigued by a fiery red diamond that seems to influence those who touch it. When a customs officer and a jeweller are gruesomely murdered, suspicion falls on a local simpleton, but Sarah and Lily believe he is innocent. Their investigation into the missing gems leads them on a perilous journey back to India, where they confront ghosts and the deadly cult of the goddess Kali.