Theodore Tinsley was an American

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 author

Author

An author is broadly defined as "the person who originates or gives existence to anything" and that authorship determines responsibility for what is created. Narrowly defined, an author is the originator of any written work.-Legal significance:...

 who wrote primarily mystery

Mystery fiction

Mystery fiction is a loosely-defined term.1.It is often used as a synonym for detective fiction or crime fiction— in other words a novel or short story in which a detective investigates and solves a crime mystery. Sometimes mystery books are nonfiction...

 stories. Tinsley wrote 27 stories featuring The Shadow

The Shadow

The Shadow is a collection of serialized dramas, originally in pulp magazines, then on 1930s radio and then in a wide variety of media, that follow the exploits of the title character, a crime-fighting vigilante in the pulps, which carried over to the airwaves as a "wealthy, young man about town"...

 for "The Shadow Magazine" pulp magazine

Pulp magazine

Pulp magazines , also collectively known as pulp fiction, refers to inexpensive fiction magazines published from 1896 through the 1950s. The typical pulp magazine was seven inches wide by ten inches high, half an inch thick, and 128 pages long...

. He also created Carrie Cashin, one of the first female detectives in pulp fiction, who appeared in Street & Smith

Street & Smith

Street & Smith or Street & Smith Publications, Inc. was a New York City publisher specializing in inexpensive paperbacks and magazines referred to as pulp fiction and dime novels. They also published comic books and sporting yearbooks...

's Crimebuster pulp magazine. An early series he wrote is the "Amusement Inc./Scarlet Ace" series that ran over 4 different pulp magazines in the 1930s.