This film noir in Technicolor, shot in the Arizona desert and California lakeside locales, perfectly captures the outer tranquility and inner turbulence of its female protagonist, played by Gene Tierney. The new wife of backwoods writer Cornel Wilde is devoted to a fault: she wants him all to herself, and calmly if inventively murders those, including children, who will intrude. "There's nothing wrong with Ellen, she just loves too much," is her mother's analysis of the daughter whose complexes range from Electra to Medea. Director John M. Stahl (who also made the intriguing The Locket, about a kleptomaniac), as Silver and Ward write in Film Noir, had an "unusual conception of his heroines as super-real, emotionally alive individuals frustrated by their dull surroundings and unimaginative men. Society might see these women as unnatural and mentally ill, but to Stahl they are profoundly provocative beings." Hence the admonition of the film's title.