Double Dragon (双截龍, Daburu Doragon - Sō Setsu Ryū) is a beat 'em up video game series originally developed and published by Technōs Japan.

Another fighting game produced by Technōs, simply titled Double Dragon, was released for the Neo Geo arcade and home console in 1995.

It takes place shortly after Double Dragon II: The Revenge and uses an 8-bit artstyle, similar to the NES ports of the earlier entries of the series.

The title was developed by Arc System Works and former Technōs staff such as producer Takaomi Kaneko, director Yoshihisa Kishimoto, character designer Koji Ogata, composer Kazunaka Yamane and programmer Kei Oyama.

A film version of Double Dragon was released in theaters in 1994, directed by James Yukich and starring Scott Wolf and Mark Dacascos as the Lee brothers.

The gameplay in most of the games takes place in a pseudo 3D perspective as seen in Renegade and later beat 'em ups, in which the player can move in four directions but is always facing left or right.

For most of the series, players take control of martial artist William "Billy" Lee, who battles against various adversaries such as gang members and rival fighters.

The Lee brothers are characterized as successors of a fictional martial art known as Sōsetsuken (双截拳, "Twin Sever Fist", also known as Sōsaiken), which combines techniques from other styles such as karate, tai chi and Shorinji Kempo.

[12] The duo were actually unnamed when the original arcade game was initially released in Japan,[13] although the names Hammer and Spike were given to them in the cabinet and promotional flyer produced by Taito for the overseas version.

Recurring members of the gang throughout the various versions of the first game include the thugs Williams and Rowper, dominatrix Linda and bald strongman Abobo.

While the arcade version of Double Dragon II: The Revenge had Willy and the Black Warriors retaliating against their earlier defeat by gunning down Marian,[18] the Famicom version replaced Willy with a nameless fighter who led a mysterious armed group following the dissolution of the original Black Warriors.

The names Williams and Rowper were derived from the characters played respectively by Jim Kelly and John Saxon in the movie Enter The Dragon.

They influenced the creation of titles such as Golden Axe, Ninja Gaiden and Final Fight, which firmly established beat 'em ups as a popular game genre.

[21][22] Double Dragon ushered in a "Golden Age" for the beat 'em up genre that took it to new heights with its detailed set of martial arts attacks and its two-player cooperative gameplay.

[4] Years later, original series creator Yoshihisa Kishimoto lamented the inconsistency in design and quality of the various versions and spin-offs of Double Dragon in games and other media.