That murder minded couple, Dr. Jeffery and Anne MacNeil, now parents, get another break in domesticity when Anne and her brother are taking a rest cure in a convalescent inn. And two of the inmates are killed. Anne defends and protects romance where she finds it, irritating the police; Jeffery, with a large dose of materia-medica, goes a-sleuthing. Trouble from a hidden marriage, plans for a competitive sanatorium and hot-house jealousies serve as background for the killings. A cosy tale.