- "Get back in one piece, people! Please."
- —Irene in Dead or Alive Dimensions
She is the main female lead in the original Ninja Gaiden trilogy for the NES, serving as Hayabusa's romantic interest and the series' damsel in distress. In the reimagining of the original NES series of Ninja Gaiden, Irene was first introduced in the 2008 title Ninja Gaiden II using the name "Sonia", before using her real name in Dead or Alive Dimensions, which marked her first visual appearence in the Dead or Alive series.
The Second TournamentEdit
Assigned by the CIA to investigate the Dead or Alive Tournament Executive Committee, Irene encountered her partner Hayabusa after he departed from Lisa Hamilton's suite on the Freedom Survivor, with information on DOATEC Germany. After Hayabusa retrieved data and Kasumi from the research facility, Irene analyzed it and both are shocked to discover that DOATEC has resurrected Hayate from his comatose state.
Kasumi wanted to go find her brother, but Hayabusa stood against the idea and slapped Kasumi. Irene rebuked Hayabusa for hitting her, but when Kasumi left anyway, she was unable to stop Hayabusa from sending Ayane after her. While Hayabusa was knocking other fighters out of the competition, Irene infiltrated DOATEC and investigated further. After the tournament, she finally meets Hayate, fully recovered from his amnesiac state.
The Third TournamentEdit
While investigating the tournament sponsers in DOATEC, Irene watched the fight between Hayabusa and Hayate with Ayane. She tried to talk Ayane into stopping the two men from having to use their Ninpo techniques on each other, but she was captured by the assassin Christie and was used as bait to lure Hayabusa away from the Tenjin Ninjas for Genra to get his hands on them. Hayabusa rescued Irene, but they were almost too late to stop Genra, prompting the Super Ninja to save them.
The Fourth TournamentEdit
Backing the Mugen Tenshin Clan on their assault against DOATEC, Irene and the CIA assisted in the raid on DOATEC's facilities. She stated that the codename for the operation is "Sonia", and asked that the shinobi come back alive.
Irene's appearence seems to have changed in Dead or Alive: Dimensions from Ninja Gaiden, to match the "anime-style" of Dead or Alive. Her eyes are now blue and larger in size, her face is rounder, her lips are now pink, and her hair is slightly longer and more layered. She also wears a more casual outfit, as apposed to the spy-styled dress in Ninja Gaiden, composing of a hot pink corset-like shirt, a green army jacket, ripped black tights, and tanned boots and mini-shirt. She is still pale-skinned, platinum blonde, and still sports her red tattoo, a belt with magazine holders, and cord necklaces, although the cores are now much shorter.
Irene is a gutsy woman who is also gifted with a knack for espionage. She is highly skilled with firearms of many different kinds, from hand guns to RPGs.
Irene is from the name Greek Ειρηνη (Eirene), which derived from a word meaning "peace". This was the name of the Greek goddess who personified peace, and was one of the Horae.
The alias, Sonia is used in the many areas of the world including the West, Russia and India. In Hindi, the name means 'golden', derived from सोना (sonā) which means 'gold', which in turn comes from Sanskrit सुवर्ण (suvarṇa; su- means 'good' and varṇa means 'color'). Her codename "Sea Swallow" is another name of the Common Tern, a seabird.
Her relationship with Hayabusa began in the original NES version of the series. As a CIA agent she was under orders to retrieve the twin Demon Statues, and afterwards fell in love with Hayabusa, ultimately running a curio shop together. In the rebooted version of the series, Irene and Hayabusa meet during the Demon Statue Incident in Ninja Gaiden II, where the two of them started off her professional partners. As things progressed, Irene slowly developed feelings for him, as evidenced from when he defeated the Demon God Vazdah the first time around and ran up to hug him.
In Dead or Alive Dimensions, Hayate and Ayane can see something going on between the two, but Hayabusa and Irene seem to keep them guessing on what their relationship entails.
Dead or Alive seriesEdit
- Dead or Alive Dimensions (non-playable, 2011)
Non-Dead or Alive appearancesEdit
Ninja Gaiden NES TrilogyEdit
In the original Ninja Gaiden trilogy, Irene is an agent of a Secret Auxiliary Unit, working under the codename "Sea Swallow". However, she is shown to have quit that job and instead began working as a CIA analyst during the events of Ninja Gaiden III: The Ancient Ship of Doom.
At some point in the series, she marries Hayabusa and helps him run an antique shop in America. However, following the re-boot, they are not married but do appear to be in a romantic relationship.
Ninja Ryūkenden OVAEdit
Voiced by Yumi Tōma, Irene appears in the Ninja Ryūkenden OVA where she is once again kidnapped, forcing Hayabusa to take up his sword to protect her.
- Irene is mentioned in the first Dead or Alive, but only through Hayabusa's biography.