late 1800’s – mid 1950’s
Mary Roberts Rinehart (1876-1958) was one of the most popular early mystery American authors. She trained as a nurse but married a doctor four days after graduation. In her spare time, while raising her three sons, she wrote for the early pulp magazines.
One of her stories was cover-featured in the debut issue of New Mystery Adventures in 1935.
When the depression hit, she turned to writing novels to earn more money.
The phrase "The butler did it," that has become a cliché, came from her novel, The Door. She is also credited with inventing the, “Had-I-but-Known" school of mystery writing.
She also created
“the Bat”, a costumed super-criminal and cited by Bob Kane as one of the inspirations for his character, “Batman”.
Many of her books were bestsellers and some, along with her plays, were adapted for movies,
“Rinehart’s literary distinction lies in the combination of love, humor and murder that she wove into her tales. . . . She helped the mystery story grow up.” —New York Times
Helen Reilly was a prolific author of mystery novels, whose career stretched from 1930 to 1962. All except her very earliest books feature New York City police Inspector Christopher McKee and were among the first American novels to stress police procedure.
Reilly had some contact with pulp magazines. Her second McKee novel,Murder in the Mews (1931), was serialized in Street and Smith's Detective Story Magazine, and she published a handful of short stories in other pulps.
However, the novel serialization could easily have been arranged by an agent or a publisher, and Reilly's degree of contact with the world of pulp writing seems restricted.