Harriet Jones is an elderly patient residing at Pembroke Hospital. She has a reputation for being a vulgar, spiteful woman and finds enjoyment through malicious gossip.
During her stay at Pembroke, Harriet was treated by Dr. Edgar Swansea. In a negligent attempt to cure Harriet, Dr. Swansea administered Lady Ashbury's vampire blood to her, informing neither Harriet nor Ashbury of his experiment. Unbeknownst to him, the vampire blood carried the infection that could eventually create a Disaster. Though Lady Ashbury was a healthy carrier, Harriet's anger at the world caused her to develop an affinity for the Red Queen and began to transform into a Disaster, beginning with showing an even stronger hatred than she possessed before.
In August 1918, Harriet's daughter Doris Fletcher visited her at Pembroke Hospital; during Doris's visit, Harriet managed to transfer the infection to her daughter, who in turn began to spread it across the West End.