American novelist and short-story writer who is best known for psychological thrillers, in which she delved into the nature of guilt, innocence, good, and evil.

Highsmith, who took her stepfather's name, graduated from Barnard College, New York City, in 1942 and traveled to Europe in 1949, eventually settling there. In 1950 she published Strangers on a Train, an intriguing story of two men, one ostensibly good and the other ostensibly evil, whose lives become inextricably entangled. The following year the novel was made into a movie by Alfred Hitchcock (Hitchcock, Sir Alfred), using a screenplay by Raymond Chandler (Chandler, Raymond) and Czenzi Ormonde. The Talented Mr. Ripley (1955) is the first of several books featuring the adventures of a likable murderer, Tom Ripley, who takes on the identities of his victims. The novel won several awards for mystery writing. Ripley also appears in Ripley Under Ground (1970), Ripley's Game (1974), The Boy Who Followed Ripley (1980), and Ripley Under Water (1991). Among her other books are The Price of Salt (1952; written under the pseudonym Claire Morgan), a tale of a love affair between a married woman and a younger, unmarried woman, and The Animal-Lover's Book of Beastly Murder (1975), about the killing of humans by animals. Highsmith's collections of short stories include The Black House (1981) and Tales of Natural and Unnatural Catastrophes (1987).

Highsmith also wrote on the craft of writing. In her Plotting and Writing Suspense Fiction (1966; revised and enlarged 1981), she held that “art has nothing to do with morality, convention, or moralizing.”