Bob Kane his first adventure strip, "Rusty and his Pals". In early 1939, DC's success with the seminal superhero Superman in "Action Comics" prompted editors to scramble for more such heroes. In response, Bob Kane conceived "the Bat-Man." Kane said his influences for the character included actor Douglas Fairbanks' film portrayal of the swashbuckler Zorro; Leonardo da Vinci's diagram of the ornithopter, a flying machine with huge bat-like wings; and the 1930 film "The Bat Whispers", based on Mary Rinehart's mystery novel "The Circular Staircase" (1908). Bill Finger joined Bob Kane's nascent studio in 1938. An aspiring writer and part-time shoe salesperson,
American comic book tropes North America. There are many definitions of a superhero, and the subject is debated by scholars and industry professionals. Peter Coogan identifies influences to comic book superheroes in the form of super-strong comic strip characters, pulp heroes, masked vigilantes dubbed "mystery men", and precursors, who lack specific elements of modern superhero convention. According to Coogan, Superman is the first character to bring together all of the necessary elements. Coogan defines the superhero as "a heroic character with a selfless, pro-social mission" who has powers, a codename, colorful costume, and usually a secret identity. American comic books can be sold through