A policeman of an anti-terror unit dies in an explosion. As he is the third of his unit to be killed, his superiors fear that they may have a leak. A rival faction of the terrorists responsible for the killings hires Noir to terminate the leak and his contact. After careful planning, Mireille and Kirika break into the terrorists' hideout, while both their targets are there. Hearing that an assassin named Noir has been hired to kill them, the policeman wonders whether there is a relation to an assassin named Noir who was last active in the 1970s. Mireille and Kirika ...
Mireille and Kirika accept a contract to kill a man suspected in the death of a young C.E.O. After making plans and entering a huge abandon hotel to make the hit, Mireille and Kirika discover it might be some kind of complex double cross as the hotel becomes filled with heavily armed men with no apparent escape.
Still bothered by the events which transpired during the Albert Dux incident, Mireille asks a trusted friend to look in to who was pulling the strings behind the surprise attack. Arriving to collect the results of the investigation, Mireille discovers that her friend and his family had all been murdered. Troubled that the information was damaging enough as to get her friend killed, Mireille seeks out answers to unlock the identity of their shadowy opponent.
Noir and the Intoccabile still have unfinished business with each other after their last face off, and each side knows that matters can only be resolved with a final showdown. To that end, both sides travel to Sicily, where Mireille and the Intoccabile met as children. But with Kirika's arm injured and Mireille fearful and doubtful about her ability to defeat the Intoccabile, does Noir have any hope of victory? And will Mireille and the Intoccabile's past play a part in the coming encounter?
When Mireille and Kirika take a contract to assassinate a crooked cop who was released on a technicality, they're shocked to discover that someone has taken down the guards...and the crooked cop as well. Mireille and Kirika are totally puzzled and there's a rumor circulating around the streets that Noir was the one who did the job. Is the rumor referring to Mireille and Kirika? Or is there someone else out on the streets who is using the codename as well...someone who could be far more dangerous than even Mireille and Kirika themselves?
Mireille and Kirika are contacted by a man within the Soldats who is willing to give them a book containing valuable information. As the two women follow up this intriguing lead, they once again come up against the "true Noir", the mysterious assassin Chloe.
The mysterious Chloe has one last mission to carry out before she goes home to Altena and the manor - she has been ordered to kill an old NATO intelligence officer. As she journeys to Switzerland to carry out her task, Chloe finds that she is not the only one who has been sent to kill Reimann, and that she may have to protect him if she wants to be the one to eventually take him out.
Kirika learns things the hard way, when she fails to heed warnings by Mireille to stop seeing the man she is attracted to, because they are currently targets of a madman who is obsessed with killing them both.
Mireille and Kirika are offered a job in Taiwan- and their employer is none other than the Soldats. Despite the danger, Noir decide to accept, hoping that working for the Soldats will help them uncover some answers. But the assignment proves to be far from straightforward when they find themselves targeted by the Taiwanese assassin Shaoli, better known as the "Cold-Blooded Killer".
Kirika and Mireille's mission to destroy the Hang Yiban triad went awry when the Hang Yiban sent their own assassin- the ruthless Shaoli, to destroy Noir. Now, Mireille has been captured by the Hang Yiban, and Kirika must work with the mysterious Chloe to free her. But even if Mireille can be rescued, Noir still has the job of eliminating both the Hang Yiban leaders, and Shaoli herself...
Mireille Bouquet decides to return home to the lovely town of Corsica to visit the old graves of her deceased family members. But while Mireille's visit is partly based on sentimentality, it is also a personal visit to get answers from the current crime lords who now govern Corsica with absolute dominion. The crime lords in power tell her that her family had a nasty altercation with a colossal entity known as the Soldats and the only person who might know anything is George Madeline, Laurant Bouquet's right-hand man from the old days when the Bouquet family controlled...
Still upset over the truths she learned in Corsica, Mireille, confused and traumatized, forces Kirika to get out of her sight, calling her a disturbing enigma. Kirika leaves, obviously distressed about Mireille's words and her own mysterious past. After receiving inside information on Chloe's motives, Kirika is warned of a trap set for her troubled friend - will she make the choice to save Mireille despite their confrontation?
Mireille and Kirika fly to Austria on a hunt for the ancient manuscript that could solve the mystery of the Soldats, but they run into a familiar face - someone who suddenly has her finger over the trigger to set off Kirika's memory.
Kirika's final guidance - in the form of a bullet - brings a rush of painful memories. Mireille finally learns the connection to their past, but fails to follow through with her original promise to kill Kirika.
Kirika collapses at the edge of a village and is taken in by an old couple who have been expecting her. There she learns about an ancient ritual, the Grand Retour, of which she is an essential part - and a threat to certain factions of the Soldats.
After Kirika departs from her care, following the truth about the deaths of the Bouquet family, Mireille tries to continue on with her daily-routine before she met Kirika but finds that extremely hard with the depressing mood that she's in. She's then approached by a member of the Soldats named Remy Braffort who would like her to join the Soldat's ranks as its chief enforcer in dealing with Altena, whom they feel is getting too radical with her methods within the organization. But Mireille tells Remy that she has beef with the Soldats and is not going to get involved ...
Priestesses from the Soldats arrive at the manor to praise Altena for orchestrating the Grand Retour. Chloe savors her time with Kirika as they don their ritual garb and practice fighting in the ruins.
After word of Mireille's arrival at the manor has reached her, Althena is ready to commence with the Grand Retour and begins the final stage of her plans that will determine the 'True Noir'. But in the Grand Retour, the rules state that only two maidens can serve as the True Noir and between Kirika, Mireille and Chloe, one of these beauties is going to have to lose out. Will Chloe and the now brainwashed Kirika succeed in removing Mireille from the game? Or can Mireille get through to her former partner in time to avoid anymore unnecessary bloodshed? Only one thing is...