Enola Holmes returns in her first adventure after the success of the Netflix movie, which has taken her back to the top of the sales charts. Enola Holmes is the sister of Sherlock and Mycroft. And just like them, she possesses intelligence, skills and detective inclinations. When Miss Letitia Glover, an emancipated woman, comes to Sherlock asking him to find out what has happened to her twin sister, it is Enola who greets her. Apparently, and according to the brief message she has received from her, her sister Felicity, married to the Earl of Dunhench, has died. But Letitia Glover is convinced that this is not true: if her sister had died, she would have known it, she would have felt it inside her.