Ninja Gaiden features a ninja named Ryu Hayabusa who seeks revenge for the death of his father and then finds himself involved in a sinister plot that threatens the entire world. The story opens with Ryu's father Ken being killed in a duel by an unknown assailant. After the duel, Ryu finds a letter written by Ken which tells Ryu to find an archeologist named Walter Smith in America. Before Ryu can find Walter, Ryu is shot and kidnapped by a mysterious woman; she hands him a demonic-looking statue before releasing him. Ryu then finds Walter, and Walter tells him of the demon statues he and Ken had found in the Amazon ruins. Walter tells Ryu of an evil demon that "SHINOBI" defeated and whose power was confined into two "Light" and "Shadow" demon statues. Ryu shows Walter the "Shadow" demon statue given to him from the woman, but during their conversation, a masked figure suddenly breaks into the cabin and steals the Shadow statue. Ryu gives chase, defeats the masked figure, and retrieves the statue; but when he returns he finds that Walter is dying and the Light statue is missing. Right after Walter dies, three armed men confront Ryu and tell him to come with them.

Ryu is taken to an interrogation room, where he meets Foster, head of the Special Auxiliary Unit of the Central Intelligence Agency. Foster tells Ryu about an over 2000-year-old temple Walter discovered in some ruins in the Amazon. He continues by saying that Walter, one day, mysteriously sealed the ruins, in which nobody has since ventured near. Foster explains to Ryu that they have been monitoring the activity of someone named Guardia de Mieux, also known as "the Jaquio", who recently moved into the temple. Using the statues, the Jaquio plans to awaken the demon and use it to destroy the world. Foster asks Ryu to go to the temple and eliminate him. After making it into the temple, Ryu discovers that the Jaquio is holding captive the woman who handed him the "Shadow" statue earlier. He orders Ryu to give up the demon statue after threatening the woman's life. Ryu is then dropped from sight through a trapdoor and into a catacomb.

After fighting his way back to the top of the temple, Ryu encounters Bloody Malth, whom Ryu defeats. While dying, Malth reveals that he was the one who dueled with Ryu's father, that his father is still alive and that Ryu will meet him as he presses onward. When he reaches the temple's inner chambers, he discovers that his father was not killed but was instead possessed by an evil figure. He destroys the evil figure, which releases Ken from its hold. Jaquio, enraged from Ken's release from the possession, shows himself; he immediately tries to kill Ryu with a fiery projectile, but Ken throws himself in front of Ryu and takes the hit. Jaquio is killed during the ensuing fight by Ryu, but then a lunar eclipse occurs, causing the demon statues to transform into the demon. After Ryu defeats the demon, Ken tells him he does not have much longer to live due to Jaquio's attack. He tells Ryu to leave him behind in the temple while it collapses and to take the woman with him. Afterwards, Foster, communicating via satellite, orders the woman to kill Ryu and steal the demon statues; she chooses to be with Ryu instead of carrying out the order. The two kiss, and the woman tells Ryu her name, Irene Lew; the two watch as the sun rises.

Ninja Gaiden was developed by Tecmo, who also developed the Tecmo Bowl and Rygar series. It was one of the first two games, alongside Tecmo Bowl, to be released by the company for the Nintendo Entertainment System (NES). The game was released in December 1988 in Japan under the title Ninja Ryukenden, whose literal translation was Legend of the Dragon Sword. It was developed and released the same time as the beat 'em up arcade version of the same name; neither of the two games were ports of each other but were parallel projects developed by different teams. According to developer Masato Kato, the term "ninja" was gaining popularity in North America, prompting Tecmo to develop a ninja-related game for the NES at the same time the arcade version of Ninja Gaiden was being developed. The NES version was directed was developed and directed by Hideo Yoshizawa (listed as "Sakurazaki" in the game's credits), who led the development teams of both this game and its arcade counterpart.

Drawing inspiration from the Mario series, Yoshizawa kept the same title but changed everything else; it became a platformer as opposed to a beat 'em up as featured in Double Dragon; the gameplay was modeled after Konami's Castlevania, which Ryu was equipped with a katana-like Dragon Sword, shurikens, and ninpo techniques such as fire wheels. In designing the protagonist Ryu Hayabusa, the development team wanted him to be unique from other ninjas. They designed him with a ninja vest in order to place emphasis on his muscles, and they furnished him with a cowl that arched outward. They originally wanted to equip Ryu with sensors and a helmet with an inside monitor to check his surroundings, but that idea was scrapped. They utilized specific locations and environment to justify the need for having a ninja for a main character. In charge of designing the graphics, Kato used the NES' technical limitations to his advantage by placing the background and objects together. The game's difficulty was set at a high level due to Tecmo's policy on increasing the challenge for Western gamers.

Yoshizawa placed greater emphasis story as opposed to the arcade version, and he wrote and designed the plot that included over 20 minutes of cinematic cutscenes – the first time an NES game contained such sequences. Tecmo called the cutscene system "Tecmo Theater", in which the game reveals the storyline between Acts through the usage of animated sequences. These sequences are used at the beginning of each Act to introduce new characters such as Irene Lew, Walter Smith, and the Jaquio. This feature uses techniques such as close-ups, alternate camera angles, differing background music, and sound effects. It was used to make the game more enjoyable for players. Unlike earlier titles such as Final Fantasy, the cutscenes consisted of large anime art on the top half of the screen with dialogue on the bottom half. This made the artistic style more reminiscent of other manga titles such as Lupin III and Golgo 13. Dimitri Criona, Tecmo USA's director of sales and marketing, said that the advantages of console games over arcade games allowed the creation of a longer game and the inclusion of cutscenes, which Tecmo trademarked as "cinema screens"; he noted the lack of motivation to drop quarters that has allowed this on home consoles, which required a different reward structure than in arcade games.

When the game's text was translated from Japanese to English, the game needed to be reprogrammed in order to accomplish this; different companies handled this process in different ways. Tecmo's Japanese writers wrote rough translations in English, and they would then fax them to the American division. According to Criona, the American division would "edit it and put it back together, telling the story in a context that an American English speaker would understand. This would go back and forth several times." Moreover, the game's text was stored in picture files instead of raw computer text, and because of the NES' hardware limitations, the English text need to be very clear and concise to fall within those limitations; many times, different words with the same meaning but with less characters had to be used. All symbols and objects were scrutinized by Nintendo of America, who had specific rules on what could be included for North American releases; for instance, any Satanic, Christian, or any other religious, sexual, or drug-related references were not allowed.

Release

Since the game's title was deemed too difficult to read for English audiences, it was renamed when it was released in Western markets. In early 1988 advertisements from Nintendo Fun Club News, Tecmo used Dragon Ninja as a tentative title for the U.S. release. They decided to use the title Ninja Gaiden when the game was released in the U.S. in March 1989; the title literally meant "Ninja Side-Story", but the game was not intended as a spin-off of the arcade version. According to an interview with developer Masato Kato, the staff, determining how to translate "Ryukenden" into English, went with Ninja Gaiden "because it sounded cool". In Europe, the game was scheduled to be released in September 1990, but censorship issues delayed its release until September 1991. It was retitled as Shadow Warriors – just as Teenage Mutant Ninja Turtles was renamed Teenage Mutant Hero Turtles – as ninjas were considered a taboo subject in Europe. Its release was a part of many ninja-related video games such as The Legend of Kage, Ninja Warriors, and Shinobi.

Upon Ninja Gaiden's North American release, Nintendo of America, whose play-testers liked the game and gave it high ratings, decided to help with its marketing. It was featured prominently in Nintendo's house organ Nintendo Power; according to Criona, it did not take a lot of effort to market the game through the magazine, nor did Tecmo or Nintendo do much else to promote it. The game's demand eventually exceeded its supply. While Tecmo anticipated that the game would be a hit, they did not realize at the time its impact it would have in the video game industry, according to Kohler, "with its groundbreaking use of cinematics". Yoshizawa would go on to develop and direct the other two sequels in the series: Ninja Gaiden II: The Dark Sword of Chaos (1990) and Ninja Gaiden III: The Ancient Ship of Doom (1991). He directed the development of the gameplay, including a feature that sent players back to the beginning of the sixth Act after losing to any of the final three bosses in the game, which was originally a glitch. The game's graphics, animations and instruction manual illustrations were done by Masato Kato; Ninja Gaiden was Kato's first project as a video game developer.

Ninja Gaiden received preview coverage in the January–February 1989 issue of Nintendo Power in its "Pak Watch" section, where it "got the highest marks of any title we've [the magazine's staff] seen in a long time", and that it was expected to be No. 1 on their "Player's Poll" quickly. The preview compared Ryu's ability to climb and spring off walls to the gameplay in Metroid. The game was unveiled at the 1989 International Winter Consumer Electronics Show in Las Vegas, and its display featured a demo of the game and a live person dressed as a ninja. Tecmo predicted that the game would be the top-selling third-party title for the NES.

The game has been ported to several other platforms, including the PC Engine, the Super NES, the Virtual Console, and mobile phones. The game was first ported to the PC Engine in 1992 and was published by Hudson Soft and released only in Japan; it featured an alternate English translation, more colorful and detailed graphics, and difficulty and gameplay tweaks. It appeared as a remake for the Ninja Gaiden Trilogy compilation for the Super NES in 1995. Some reviewers appreciated the redrawn graphics and music in this version, but others found them to be an inadequate effort. Electronic Gaming Monthly reviewers compared it unfavorably to another updated NES remake, Mega Man: The Wily Wars; they called the version "an exact port-over with no noticeable enhancements in graphics, sound and play control". Along with the other two games in the NES Ninja Gaiden trilogy, the original version was featured as an unlockable game in the 2004 Xbox remake. It was released on Wii's Virtual Console on April 10, 2007 (2007-04-10) in Japan and on May 14, 2007 (2007-05-14) in North America. Europeans, Australians, and New Zealanders have been able to purchase the game as part of "Hanabi Festival" on September 21, 2007 (2007-09-21). The PC Engine version was released for Virtual Console on April 21, 2009 (2009-04-21). The game will be released for the Nintendo 3DS Virtual Console, and was originally set for a November 8 release. However, it was delayed until December 13, 2012, making Tecmo's second classic game release for the 3DS after Mighty Bomb Jack, which released on December 6.

Ninja Gaiden received strong publicity in Nintendo Power in 1989 and 1990. It was featured on the cover of the magazine's March–April 1989 issue and was referenced in the following issue in a Howard and Nester comic strip. It was one of the featured games in both March–April and May–June 1989 issues of the magazine; both issues included a walkthrough up to the fifth Act, a review, and a plot overview. Underlining the game's difficulty, it appeared in several issues in the magazine's "Counselor's Corner" and "Classified Information" help sections. The game debuted at No. 3 on its "Top 30" list for July–August 1989, behind Zelda II: The Adventure of Link and Super Mario Bros. 2; it stayed at No. 3 in the following September–October 1989 issue. The game was featured in the "Nintendo Power Awards '89" as one of the top games that year. It was nominated for "Best Graphics and Sound", "Best Challenge", "Best Theme, Fun", "Best Character" (Ryu Hayabusa), "Best Ending", and "Best Overall"; and it won for "Best Challenge" and "Best Ending". In its preview of Ninja Gaiden II: The Dark Sword of Chaos, the magazine said that "the colorful, detailed and dynamic cinema scenes of the original Ninja Gaiden set a standard for action game narration that has since been widely emulated. These cinema scenes made Ninja Gaiden play almost like a movie."

The game received strong reviews and publicity from other video gaming magazines at the time. In a review from VideoGames & Computer Entertainment, the presentation and gameplay was compared to Castlevania, while the cinematic cutscenes were compared favorably to Karateka and other computer games by Cinemaware. The review praised the game's animation in these cutscenes and noted Tecmo's usage of close-ups and body movements. The reviewer said that while the cutscenes were not fluid, they were effective and entertaining and gave important information as to what the player was supposed to do. He appreciated that the game had unlimited continues which slightly offset its difficulty, but he criticized it for having overdetailed background graphics especially in the indoor levels, saying that some bottomless pits and items in these levels become slightly camouflaged. From July to October 1989, the game was listed at No. 1 on Electronic Gaming Monthly's "Top Ten Video Games" list; it fell to No. 2 on the list behind Mega Man 2 in the following November issue. In their "Best and Worst of 1989", it received awards for "Best Game of the Year" for the NES and "Best Ending in a Video Game" for all consoles. The staff said that Ninja Gaiden "proved to be an instant winner" with its cinematic cutscenes and unique gameplay. They added that the game's climax was better than some movies' climaxes at the time and that it established continuity for a sequel, which would be released the following year. Later in June 1994, the magazine ranked it at No. 4 in a special list of "Top Ten Most Difficult Games" of all time for all consoles.

Ninja Gaiden was featured on the cover of the pilot issue of UK magazine Mean Machines in July 1990; the magazine was distributed as part of the July 1990 issue of Computer and Video Games. In its review, Julian Rignall compared the game to its beat 'em up arcade counterpart, which was titled Shadow Warriors. He noted that the game has great graphics that feature diverse backgrounds and character sprites; he gave special praise to its usage of cartoon-like animation sequences between Acts in which the game's plot unfolds. He enjoyed the game's difficulty especially with the bosses, but he noted that the game will seem tough at first until players get accustomed to the controls. He criticized the game for its sound, which he said did not fit with the graphics and was "racy", but said that "what's there is atmospheric and suits the action". He highly recommended the game to fans of the beat 'em up and combat genres.

The game (the NES version now officially titled Shadow Warriors in Europe) was reviewed again in Mean Machines' July 1991 issue. In the review, Matt Regan and Paul Glancey praised the game's detailed and animated character sprites and its difficulty level. Regan was impressed with the game's high standards of gameplay, sound, and overall depth; he noted the game's frustrating difficulty but pointed out that it has unlimited continues. Glancey compared the game to the 1990 NES version of Batman with the similarities of wall-jumping mechanics; he said that its graphics were not as well-developed as Batman's but were still satisfactory. He praised its detailed sprites and their animations along with the "Tecmo Theater" concept, noting that the cutscenes "help supply a lot of atmosphere". He said that it is of the best arcade-style games on the NES as well as the best ninja-related game on the system.

The game received some praise and criticism in the August 1991 issue of German magazine Power Play. The review praised the game for its attention to detail and challenge and noted that players need to master certain gameplay skills to move on. Criticisms included a "lack of variety" and dullness in gameplay, in which it was compared to a "visit to the tax office". The PC Engine version was briefly mentioned in the December 1991 issue of Electronic Gaming Monthly as part of a review of games that have been released outside the U.S. They noted the faithful translation from the NES version as well as the revamped and more detailed graphics; they said that "PC Engine owners should not miss this one!"

Legacy

In 2004, Tecmo began releasing low-priced episodic installments of Ninja Gaiden for AT&T and Verizon mobile phones on both BREW and Java platforms. The official English Tecmo Games mobile website advertised it for a future release along with a mobile version of Tecmo Bowl. They planned to release the entire game throughout 2004 in a series of four installments – similar to what Upstart Games did when they ported the NES version of Castlevania to mobile phones. The port featured the same visuals and soundtrack found on the NES version, and each installment was to consist of several levels of gameplay at a time. The first installment, titled Ninja Gaiden Episode I: Destiny, was released on July 15, 2004 (2004-07-15), and it included only the first Act from the NES version but added two new levels. The second installment was planned to be released in North America and was previewed by GameSpot in September 2004, but it – along with the third and fourth installments – was never released.

The mobile phone port of Ninja Gaiden was met with some praise and criticism. IGN's Levi Buchanan and GameSpot's Damon Brown praised the port for its accurate translation from the NES to mobile phones, saying that the gameplay, graphics, and cinematic cutscenes remain true to the NES version. They praised the game's controls, despite the game's omission of the ability to duck so that pressing "down" on the phone's directional pad could be used for secondary weapons; Brown said the port had better controls than most other mobile phone games at the time. They both criticized the port for its lack of sound quality, but Buchanan said that this was not Tecmo's fault. In a preview of the port, GameSpot's Avery Score pointed to generally inferior American-made handsets as the reason for its sound shortcomings.

Retro Gamer took a look back at Ninja Gaiden in its March 2004 issue, in the midst of the release of the 2004 Xbox remake. They said that the game broke the mold of conventional video game titles by including a plot with cinematic cutscenes added between gameplay segments. They added that the concept of adding cinematics for a game's introduction, plot, and ending was a new concept which "naturally impressed the gaming public". They noted the game's high difficulty level, saying that the game "threw up an immense challenge even for the veteran gamer, and almost dared you to complete it mentally and physically intact". Chris Kohler, in his 2004 book Power-Up: How Japanese Video Games Gave the World an Extra Life, said, while it wasn't as far-reaching as Tecmo Bowl, "it ended up revolutionizing video games with its courageous, unique, and trailblazing use of cinema scenes".

Upon its release on the Virtual Console, Ninja Gaiden was met with high praise, especially for its elaborate story, amount of narrative, and usage of anime-like cinematic sequences. Some critics have bemoaned its gameplay for being too similar to Castlevania; similarities include identical displays on the top of the screen, items contained in breakable lanterns, and a nearly identical "secondary weapons" feature. A 1UP.com review noted that the two games have different dynamics and that several actions possible in Ninja Gaiden would be impossible in Castlevania. Contemporary reviews have considered the game "groundbreaking" for its pioneering use of stylized cutscenes, high quality music, and dark atmosphere. One review said that the game makes up for its high difficulty level with good gameplay. IGN said that it is one of the best platforming video games of all time.

Reviewers have criticized the game for its high and unforgiving difficulty level especially late in the game. A review from 1UP.com referred to the latter levels as an "unfair display of intentional cheapness". In his review of the Virtual Console version, GameSpot's Alex Navarro said "the game will beat you to a pulp" and that it "assaults you time and time again with its punishing difficulty, insidiously placed enemies, and rage-inducing boss fights". According to his review, the game starts easy, but the difficulty starts to increase halfway through the second Act and continues through the sixth Act; Navarro describes the sixth Act's difficulty as being "one of the bottom levels of gaming hell". IGN said that this game was one of the most difficult video games of all time, setting the trend for the rest of the series; however, they pointed out that its difficulty and graphics are "defining characteristics [that] have carried over through the years into modern day [Ninja] Gaiden sequels".ScrewAttack listed the game as the seventh hardest title in the NES library.

Over fifteen years after its creation, Ninja Gaiden has maintained its position as one of the most popular games for the NES. A 2006 Joystiq reader poll, with over 12,000 votes, listed the game at No. 10 in a list of top NES games. Another reader poll from GameSpot listed the game at No. 10 in its top 10 NES games list. It was No. 17 on IGN's "Top 100 NES Games" list. In August 2001 in its 100th issue, Game Informer listed the game at No. 93 in their "Top 100 Games of All Time" list. In 2006 Electronic Gaming Monthly featured a follow-up to their "The 200 Greatest Videogames of Their Time", in which readers wrote in and discussed games they felt were ignored on the list; the game was listed at No. 16 in the top 25 games discussed. At the end of 2005, Nintendo Power ran a serial feature titled "The Top 200 Nintendo Games Ever". The list, which included games for all Nintendo systems, had the game at No. 89. In August 2008, the same magazine ranked it the tenth best NES game of all time; they praised the gameplay and described the cinematic cutscenes as revolutionary for its time. The game's music received honorable mention in IGN's list of "Best 8-Bit Soundtracks". Its introduction was featured in IGN's "Top 100 Video Game Moments" list at #53; it was also listed as the second best video game cutscene of all time in Complex magazine.

Nintendo Power honored the game in its November 2010 issue, which celebrated the 25th anniversary of the NES. The magazine listed its box art, which depicts a ninja with a burning city in the background, as one of its favorite designs in the NES library. The magazine's Editor in Chief Chris Slate was equally impressed by the game's box art. He also reminisced the game's high level of difficulty with its re-spawning enemies and enemy birds that knocked players into pits, saying this game "may have taught me how to curse". He further praised gameplay features such as clinging on walls and using ninpo techniques, and he noted the game's cinematic cutscenes, including the ominous opening sequence that featured two ninjas who launch into the air at each other and clashing their swords in the moonlight. He said that "Ninja Gaiden was about as cool as an 8-bit game could be, especially for ninja-crazed kids of the '80s who, like me, had worn out their VHS copies of Enter the Ninja". In a July 2011 issue, Retro Gamer listed the game's opening as one of the most popular ones at the time. The magazine noted how its usage of cutscenes, animations, and overall presentation put the game above most other action titles at the time. While it lauded the controls and gameplay elements, as with other reviews, it criticized the difficulty, calling it "one of the most challenging games on the console". It noted how defeated enemies re-spawn in certain spots, how enemies are placed on the edges of platforms, and the structure of the final level.

In July 1990 Scholastic Corporation published a novelization of Ninja Gaiden under the Worlds of Power series of NES game adaptations, created and packaged by Seth Godin under the pseudonym "F. X. Nine". Godin and Peter Lerangis, under the pseudonym "A. L. Singer", wrote the novelization. As with the other Worlds of Power books, the amount of violence present in the video game was toned down in the novelization, because Godin and Scholastic were concerned that some of the material in the video game was inappropriate for a young audience. The novel did not strictly adhere to the game's storyline; for instance, the ending was changed so that Ryu's father survived. Ryu's father remained alive in the story because Godin believed that the revised ending was consistent with the Worlds of Power character and as real-life fathers Godin and Lerangis felt reluctance to leave Ryu without a father. The book's cover, otherwise a replication of the North American box art, had the kunai held in Ryu's front hand was airbrushed out, leaving him to prod the air with an empty fist.

A soundtrack CD, Ninja Ryukenden: Tecmo GSM-1, was released by Pony Canyon in February 1989. The first half of the CD starts with an arranged medley of the game's music. It then continues with enhanced versions of the game's music which utilized stereophonic sound and additional PCM channels. The remainder of the CD features music from the arcade version.

Ninja Ryukenden: Tecmo GSM-1 track listing
No.	Title	Length
1.	"NINJA GAIDEN ARRANGE VERSION"	6:46
2.	"Moonlight Duel"	0:20
3.	"A Decision – Father's Letter"	0:47
4.	"The Ninja Dragon"	0:55
5.	"Mysterious Woman"	0:24
6.	"Heroism – The Approaching Evil"	0:49
7.	"Reflection"	0:41
8.	"... Suddenly!"	0:04
9.	"Like a Hurricane"	0:11
10.	"Ambush – Pursuit of a Nightmare"	0:50
11.	"Eyecatch"	0:04
12.	"CIA"	0:50
13.	"The Temple of Darkness length13 = 0:20"
14.	"Ryu's Determination"	1:31
15.	"Danger"	0:46
16.	"Assault – Stealthy Devil"	0:44
17.	"Malth – The Crimson Terror"	0:34
18.	"The Hidden Truth"	0:42
19.	"Tragic Fate"	0:32
20.	"Requiem"	0:44
21.	"Jaquio's Threat"	0:52
22.	"Offense and Defense – To the Hideout of Death"	0:42
23.	"The Demon's Curse"	0:34
24.	"Dilemma – The Battle of Ordeal"	0:46
25.	"To the End of Combat"	0:47
26.	"Irene – Prelude to Dawn"	1:05
27.	"Insert Coin"	0:04
28.	"Game Start"	0:05
29.	"Shadow Soldier"	3:07
30.	"Sumo Wrestler"	1:46
31.	"Round Clear 1"	0:07
32.	"Pat"	1:54
33.	"I am Man"	1:41
34.	"Round Clear 2"	0:07
35.	"Casino"	2:56
36.	"Na-n-to"	2:06
37.	"Round Clear 3"	0:07
38.	"Nature's Symphony"	3:13
39.	"Round Clear 4"	0:07
40.	"Chasing Him Until the Very End"	2:46
41.	"Round Clear 5"	0:07
42.	"Humming of the Devil"	2:32
43.	"Last Fight"	3:34
44.	"Time Up"	0:05
45.	"Game Over"	0:04
46.	"689, Everybody Likes ... Sukiyaki?"	1:46
47.	"The Most Unexpected Thing in the World"	1:09
48.	"The Sun Rises Over the Hills"	2:04
Total length:		0:54:47