In Victorian England, a fortune now depends on which of two brothers outlives the other—or can be made to have seemed to do so.

Working-class British housewife Myra Savage reinvents herself as a medium, holding seances in the sitting room of her home with the hidden assistance of her under-employed, asthmatic husband, Billy. In an attempt to enhance her credibility as a psychic, Myra hatches an elaborate, ill-conceived plot to kidnap a wealthy couple's young daughter so that she can then help the police "find" the missing girl.