When 16-year-old Laura della Scala learns that her older sister, Beatrice, has drowned, she is given no time to grieve. Instead, Laura's father removes her from the convent where he forcibly sent her years earlier and orders her to marry Beatrice's fiancé, a repulsive old merchant named Vincenzo. Panicked, Laura betrays a powerful man to earn her way into the Segreta, a shadowy society of women who deal in only one currency—secrets. The Segreta seems like the answer to Laura's prayers. The day after she joins their ranks, Vincenzo is publicly humiliated and conveniently exiled. Soon, however, Laura begins to suspect that her sister's death was not a tragic accident but a cold-blooded murder—one that might involve the Segreta and the women she has come to trust.