First appearance

In American comic books and other stories with a long history, first appearance refers to the first issue to feature a fictional character. These issues are often highly valued by collectors due to their rarity and iconic status.

First appearances of popular characters are among the most valuable comic books in existence. Of the "ten most valuable comic books" listed in the spring 2002 issue of The Overstreet Comic Book Price Guide, seven are first appearances of popular superheroes. Another, Marvel Comics #1 (October 1939), is the first appearance of the Golden Age Human Torch but is more noteworthy as the first comic book published by industry giant Marvel Comics.

It can take many years for a character to attain sufficient popularity after their first appearance to be considered "iconic." By the point a character reaches that level of popularity, it is common for few copies of their first appearance issues to remain. Furthermore, even fewer of those remaining copies will be in the pristine condition prized by collectors. What few remain can be worth thousands of dollars to interested collectors. For example, in 2004, a copy of Flash Comics #1 (January 1940), the first appearance of The Flash, was auctioned for $42,000 and a copy of Captain America Comics #1 (March 1941), the first appearance of Captain America sold for $64,400. In 2010, another copy of Flash Comics #1 sold privately for $450,000.

The first appearance of Superman, Action Comics #1 (June 1938), has been regarded as the "holy grail" of comic books, due to its rarity (fewer than one hundred copies are thought to exist) and cultural significance. Superman is widely considered to have solidified, if not created, the superhero archetype; therefore, his first appearance is not only important to fans of the character but to fans of superheroes and comic books as a whole. Well-preserved copies of Action Comics #1 have been sold at auction for record-breaking prices. A copy graded at 8.0 ("very fine") on the 10-point scale typically used by collectors was sold at auction for $1,000,000 in 2010. Even a copy graded at a much lower 5.5 ("fine minus") sold for $956,000 in 2016.

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