Siren (or Forbidden Siren as it is known in some areas, such as European release) was the first game released in the Siren video game series. It was released in 2003 in Japan and later in other countries exclusively on the PlayStation 2.
Siren is set in a remote Japanese mountain village named Hanuda , which is described as being a very traditional and particularly exclusive society. Following the interruption of a ritual in the forest near midnight and a subsequent earthquake, the village teeters between time and space, with an infinite sea of red water in place of the usual surrounding mountains. The crux of the story focuses on the efforts of Hisako Yao, the leader of a local religion, to resurrect or re-awaken a being known as Datatsushi through an occult ceremony. The siren of the title is the call of Datatsushi, summoning the residents of Hanuda to immerse themselves in the red water, thus creating an army of subordinates called shibito . The shibito then go about building a nest to house the corporeal form of Datatsushi once it is summoned, as well as killing and converting any living humans left in Hanuda. The story is told through the perspectives of ten survivors, some of whom are natives of Hanuda, and is presented out of chronological order over the three days in which the mystery takes place.
Siren is divided into several scenarios, each taking place in one of Hanuda's ten sublocations, and organized chronologically in a table called the Link Navigator. In order to complete a scenario, the player must accomplish a primary mission objective that usually involves reaching an exit point, subduing certain shibito, or finding an item. Objectives in different scenarios are interconnected via a butterfly effect, and a character's actions in one scenario can trigger a secondary objective in another. Examples of such actions include obtaining keys, unlocking doors, or otherwise interacting with items unrelated to the current mission objective. Scenarios can be replayed any number of times once completed.
The game's defining feature is the characters' collective ability to "sightjack," or see and hear from the perspectives of nearby shibito, humans, and other creatures. The process is similar to tuning into a radio frequency, with the left analog stick serving as the dial. The clarity and location on the dial of each target depend on the distance from and orientation to the player, respectively. Once a signal is found, it can be assigned to one of the controller's four face buttons to easily switch between multiple signals. Via sightjacking, the player can discover a shibito's position, patrol route, locations and items of interest. However, the player is unable to move during this time and thus vulnerable.
Avoiding shibito is heavily emphasized in order to progress through the game. Characters can walk silently, avoid the use of flashlights during dark scenarios, and crouch behind objects to elude detection. Certain mission objectives require the use of items and the environment to create distractions that will displace shibito from their usual positions. Others require the player to escort and issue commands to a non-playable character. The player can also shout at any time in order to call the attention of nearby shibito. Also within most levels, the player can hide in certain places such as cupboards and also lock doors to prevent shibito from entering, although shibito will eventually break the lock if attempting to open the door.
When a shibito hears a suspicious sound, it will search in the general direction of the sound's origin. If a character enters the shibito's line of sight, it will actively pursue the character and attempt to kill him either with a weapon or by strangulation. The shibito will also shout to alert others nearby shortly after it spots the character. Once the character has remained out of sight for a period of time, the shibito will give up and resume its usual habits.
Weapons are available. Weapons range from items such as a poker or crowbar, to firearms. In melee combat, the player can use either a regular quick attack or a slower, more powerful attack. Shibito will hear shots and attempt to investigate. While shibito can be defeated in combat, they cannot be killed and will reanimate after a period of time, briefly remaining in a suspicious state. Similarly, if a character is injured, he can recover after a period of time. Characters will lose stamina during combat and while running.
The in-game map displays the surrounding area and the player's directional orientation, though it does not indicate the player's current location (only the start and end points). The player has to distinguish where he is by orienting himself with certain landmarks on the map.
There are also miscellaneous items scattered throughout each scenario that give the player further insight into the story's background. Once obtained, these items are placed into a catalog called Archives and can be viewed at any time during the game.
- Kyoya Suda
An inquisitive teenager who is fascinated by urban legends. Sixteen-year-old Kyoya travels to the Hanuda area in search of an unnamed village where a massacre occurred many years ago. His relationship with Miyako Kajiro forms the central storyline of the game - the two meet early on when he helps her escape from her sister's fiancé Jun, and then spends most of the game trying to escort her out of Hanuda. Kyoya is the main character in the game, and the character who finally confronts Datatsushi in combat at the end of the game.
- Tamon Takeuchi
34-year-old Takeuchi is a professor in folklore and legends at a Tokyo university, and was born in Hanuda. He lost his parents as a child during the first attempt at the occult ceremony and the landslide that followed. He has returned to Hanuda, ostensibly to study local folklore, but searching for the truth behind what happened to his parents is his true goal. Takeuchi begins with his .38-caliber revolver as a starting weapon, which trades hands with several other characters by the end of the game.
- Yoriko Anno
Yoriko is a university student from Tokyo, and a pupil of Takeuchi's. She insists on accompanying him to Hanuda, and is caught up in the events that transpire. Yoriko is twenty-two years old, has a huge crush on her teacher, and is quite abrasive and hysterical at times. However, she has a good heart, and has a surprising reserve of courage when called upon to fight. In the ending of the game, she is reunited with her teacher, having been separated from him, and breaks into the Takeuchi house, beats his undead parents with a baseball bat and pulls him away.
- Kei Makino
Twenty-seven-year-old Makino (born Takaaki Yoshimura) is a priest in the local religion and the identical twin brother of Shiro Miyata, with whom he has a frosty relationship as they were raised by different parents. He is killed by his brother late in the game's storyline. This is a matter of some confusion amongst players of the game, since Makino's death is never explicitly shown on-screen. In fact, before the scene in which his death takes place fades to black, Miyata has the gun to his own head, so the sound of the resulting shot gives the impression that he has committed suicide. Also, there are further levels playable as "Kei Makino" following this scene. Miyata takes Makino's place on these levels, dressed in his brother's robes.
- Shiro Miyata
The player is first introduced to twenty-seven-year-old Dr. Miyata (born Katsuaki Yoshimura ) when he awakens in the forest next to a shallow grave. He was having a relationship with a nurse named Mina Onda and, for reasons which are never fully explained in the game, strangled and buried her in the woods. However, the corpse turned into a shibito, and clawed its way out of the grave. Late in the game, following a tense confrontation, Miyata kills his twin brother and takes his clothes, assuming his identity as Kei Makino. Eventually, he gives his life to end the suffering of long dead corpses, the villagers who would not bend to the will of Datatsushi.
- Risa Onda
Risa is a weak, slender twenty-one-year-old woman. She was born in Hanuda, but moved to Tokyo later in her life. She goes back to Hanuda to visit her twin sister, Mina, who still lives and holds a career there. Caught up in the aftermath of the ceremony, she meets up with Shiro Miyata, who is also looking for Mina, and they head to the hospital to search for her. Risa makes a close encounter with her sister, who is now a hideously deformed shibito brain, but manages to escape and take refuge within the hospital. Eventually, Mina manages to trap Risa in a hospital room, and through a psychic channeling, she shows Risa the truth about her connection with Shiro Miyata. Later on, Risa is killed by Miyata while under the control of her shibito sister and turns into a shibito herself.
- Mina Onda
While Mina is not a playable character and is never seen as a human, she plays a large part in the game. She is the identical twin sister of Risa Onda. By the time she is introduced into a level of the game, Mina has become a "Shibito Brain" (A psychic controller of lower Shibito), who stalks the hallways of the hospital looking for Risa and Miyata. The shovel she carries as a weapon is likely to be the same one that Shiro Miyata used to bury her prior to the events of the game. Several levels in the game revolve around escaping, defeating or subduing her, and she is arguably the most powerful shibito in the game.
- Hisako Yao
Hisako is the woman behind the legend of Yaobikuni, a nun granted immortality because she ate the flesh of a merman. Although she appears to be in her twenties, she is actually well over 1000 years old. When Datatsushi appeared in Hanuda in 684 AD during a great famine, Hisako was one of the villagers who ate his flesh as he lay dying. As a result, she was cursed by Datatsushi to live forever. Hisako initiates the ceremony that triggers the events of the game. Her advanced age has caused her to forget much of her real purpose, which explains her benevolent actions towards Kyoya in the early part of the game.
- Miyako Kajiro
This fourteen-year-old is the latest in a line of special girls born to the Kajiro family whose sacrifice is needed to resurrect Datatsushi. Miyako is eventually sacrificed by Hisako Yao as part of the ceremony to awaken her god, but her spirit continues to assist Kyoya as he attempts to defeat Datatsushi. She is blind, and can only see by sightjacking.
- Reiko Takato
A twenty-nine-year-old school teacher from the local elementary school, Takato was conducting an outing (star-gazing) with her pupil Harumi Yomoda when the earthquake hit. She lost her own child in a terrible accident several years ago, and she sees Harumi as a surrogate daughter that she must protect at all costs. Takato eventually gives her life to save Harumi, but is resurrected as a shibito. She later chases her pupil out of the Tabori settlement, and attacks Takeuchi when he struggles with transformation. Even in death however, her protective instincts win out, and she saves Harumi once again from Eiji Nagoshi, the school principal turned shibito.
- Harumi Yomoda
Harumi is a local ten-year-old schoolgirl gifted with a form of ESP related to sightjacking. She was on a school outing to study star constellations when the earthquake hit, and becomes trapped in the school along with her teacher Reiko Takato. Eventually, Harumi escapes the netherworld and ends the game as Takeuchi began it: wandering alone and orphaned through the aftermath of a natural disaster. Because her bloodstream is never exposed to any of the red water during the game's story, she is the only character who can return from the netherworld to the real world.
- Akira Shimura
Shimura is an old man of seventy years who has lived in Hanuda for his entire life. He lost his wife and son in the earthquake in 1976, and carries the pain of this loss, and his own failure to prevent the ceremony which caused it, even in his advanced years. A dedicated game hunter, Shimura carries a rifle with him at all times during the game. He knows much about the ceremony and his dislike of the local religion has made him a veritable hermit. He is quite gruff and cantankerous, but would go to any lengths to avoid becoming a monster. Faced with the endless red sea filled with shibito, and realising there is no way out of Hanuda, Shimura shoots himself to escape the horror of transforming into one of the undead. This is to no avail, however, and he later returns to life as a shibito.
- Naoko Mihama
Twenty-eight-year-old Mihama (born Naoko Tanaka) is a former model and current B-list celebrity who is in Hanuda filming a cable TV show called Occult Japan (Darkness Japan in the Japanese version). She is very vain and self-centered, and due to the fierce competition in her profession, will go to any lengths to preserve her youthful looks. Driven mad by the events, Mihama eventually submerges herself in the red water, in a misguided bid to stay forever young.
- Tomoko Maeda
Tomoko is a fourteen-year-old (seventeen-years-old in the US release) middle school student who has run away from home following an argument with her parents. Now, lost in the underworld of Hanuda, the disagreement is forgotten and she tries to find her way home to her family. Discovering that they are at the local church, having searched for her, Tomoko makes her way there (but not without difficulties). She finally reaches the church, but by then she has already become a shibito, and the sight of her knocking on the window with bloody tears running down her face terrifies her parents. They later join her as shibito, and the three take over an abandoned house to live "happily ever after" - going about their daily routines as the living dead in a hideous twist.