Alongside her husband, Mrs. Henman owned a small apartment building in the Strand, consisting of four rooms, including their own, and a basement. While her husband was the official caretaker of the complex, Mrs. Henman often had contact with the inhabitants of their building, helping out whenever she could.
Over time, she grew a strong affection for Byron Cashan, one of the tenants and the most respected music critic in London. The two started an affair, of which Cashan's neighbours, Mr. and Mrs. Bloomfield were aware, although Mr. Henman never suspected anything.
In 1868, Mrs. Henman found Cashan's lifeless body inside his room, while both the door and window had been locked from the inside. The Assassins Jacob and Evie Frye investigated the perplexing murder, eventually uncovering that another inhabitant of the building, David Golden, had used a poisoned candle to commit the murder.