The Butterfly is a hard-boiled novel by author James M. Cain published by Alfred A. Knopf in 1947. The story is set in rural West Virginia in the late 1930s and concerns a mystery surrounding an apparent case of father and daughter incest.

James Mallahan Cain was an American novelist, journalist and screenwriter. He is widely regarded as a progenitor of the hardboiled school of American crime fiction.