Set in London in the early 22nd century, this novella depicts the troubles of two lovers, Denton and Elizabeth. Elizabeth is a well-to-do woman with many connections, but Denton is only a middle-class worker. Elizabeth's father strongly disapproves of the match, and orders a hypnotist to hypnotize his daughter into thinking that she is in love with another. When the scheme is found out, Denton and Elizabeth elope, leading to a string of events that take them from the top of London society to horrifying depths of "underneath" London. (Summary by WoollyBee)