Cassia Hal's life shatters when her brother's lover--her best friend--betrays her. In a twist of fate, she returns to the past and vows revenge, but keeping her brother from falling in love with the villainess proves difficult. As hope fades, an unexpected hero arrives: Grand Duke Cain, who was executed for treason in her past life. As she uncovers the truth about their intertwined fates, Cassia realizes he may be the key to altering her destiny.