Batman
The first Batman story, "The Case of the Chemical Syndicate", was published in "Detective Comics" #27 (May 1939). Finger said, "Batman was originally written in the style of the pulps", and this influence was evident with Batman showing little remorse over killing or maiming criminals. Batman proved a hit character, and he received his own solo title in 1940 while continuing to star in "Detective Comics". By that time, Detective Comics was the top-selling and most influential publisher in the industry; Batman and the company's other major hero, Superman, were the cornerstones of the company's success. The two characters were featured side-by-side as the stars of "World's Finest Comics", which was originally titled "World's Best Comics" when it debuted in fall 1940. Creators including Jerry Robinson and Dick Sprang also worked on the strips during this period.
DC Comics
Wheeler-Nicholson's third and final title, "Detective Comics", advertised with a cover illustration dated December 1936, eventually premiered three months late with a March 1937 cover date. The themed anthology series would become a sensation with the introduction of Batman in issue #27 (May 1939). By then, however, Wheeler-Nicholson had gone. In 1937, in debt to printing-plant owner and magazine distributor Harry Donenfeld—who also published pulp magazines and operated as a principal in the magazine distributorship Independent News—Wheeler-Nicholson had to take Donenfeld on as a partner in order to publish "Detective Comics" #1. Detective Comics, Inc. was formed, with Wheeler-Nicholson and Jack S. Liebowitz, Donenfeld's accountant, listed as owners. Major Wheeler-Nicholson remained for a year, but cash-flow problems continued, and he was forced out. Shortly afterwards, Detective Comics, Inc. purchased the remains of National Allied, also known as Nicholson Publishing, at a bankruptcy auction.