Satsuriku no Tenshi

Rachel在醫院中醒來，卻失去記憶，被迫在地下室各層展開致命的犧牲遊戲。

After visiting a hospital for counseling, Rachel wakes up in an unfamiliar building with no memory of how she got there. She is told by a voice over an intercom that she will be the "sacrifice" for the inhabitants of the upper floors, and she rides an elevator from her current floor of B7 to B6. On B6, she encounters a insane, bandaged man wielding a scythe and she is barely able to escape to floor B5. On B5, she encounters Danny, who claims to be her doctor. However, it is clear that Danny is insane and obsessed with Rachel's eyes, intending to imprison her in B5. After Danny reveals her parents are dead, the shock seems to trigger Rachel's memories. The scythe wielding man then arrives and kills Danny, and the intercom announces that the man is now the new sacrifice due to violating a rule by leaving his designated floor and attacking an inhabitant of another floor. The man attempts to flee in the elevator but it is sealed. Deciding that she shouldn't be allowed to live, Rachel approaches the man and asks him to kill her. (Source: Wikipedia)

Zack與Rachel探索B4墓地，揭開Rachel的真名與Isaac的身份。

Realizing that he will need Rachel's help to escape the building, the man introduces himself as Zack and agrees to kill Rachel once they escape. They both travel up to B4 where they find a graveyard, which includes a gravestone with Rachel's name on it. They both split up to investigate the area, with Rachel finding a library while Zack destroys many of the gravestones out of boredom. Rachel finds notes promising her that the writer knows her true wish, as well as files documenting other people who have been in the building, including her and Zack, whose real name is Isaac Foster. With Zack's help, Rachel is able to unlock a door to proceed further into the building while Zack is approached by a masked boy who is angry at him for destroying the gravestones. (Source: Wikipedia)

扎克在與艾迪戰鬥時發誓要殺死蕾切尔

Zack briefly battles the boy, named Eddie, who wants to kill Rachel and bury her out of love for her. Eddie then flees and confronts Rachel, offering to grant her wish for death. However, Rachel hesitates when she realizes Zack won't be able to escape if she lets Eddie kill her. Zack manages to track the both of them down and swears to God that he will be the one to kill Rachel, and he mention of "God" immediately convinces Rachel to side with Zack. Furious at Rachel's rejection of him, Eddie turns off the lights to the floor and attempts to attack using the darkness as an advantage. Zack instructs Rachel to turn the lights back on, and she manages to steal Eddie's remote control. With the lights back on, Zack is easily able to kill Eddie. They proceed to the elevator up to floor B3, where they enter a prison-like environment. (Source: Wikipedia)

B3的殘虐典獄長凱西將瑞秋和扎克投入致命陷阱作為懲罰。

Rachel and Zack discover that B3 is controlled by Cathy, a sadistic prison warden who forces the pair through various obstacles and booby traps as punishment for their crimes. In the first room they enter, Zack is trapped in an electric chair and is repeatedly shocked, with Cathy giving Rachel a hint on how to rescue him. Rachel figures out that the dummies in the room are controlling the chair. Upon destroying the dummies, Zack is freed and the door to the next room is unlocked. They enter and are trapped in a gas chamber slowly filling with poison gas. Cathy explains they must solve a puzzle to escape and they have one gas mask to share, but they have a limited time before she releases an even deadlier poison gas that renders the mask useless. Rachel seemingly solves the first stage of the puzzle by balancing a scale, but she begins to succumb to the gas as the time limit runs out. (Source: Wikipedia)

Rachel和Zack逃出毒氣室，面對Zack因藥物引發的暴力發作

Rachel notices that an air vent has opened and Zack boosts her up where she recovers a keycard. However, in his haste to open the door, Zack accidentally breaks the card as time runs out and the second gas starts pumping into the room. Rachel deduces that the gas must be flammable and creates a spark, triggering an explosion that blows out the door and allows her and Zack to escape. Weakened by the gas, Rachel and Zack decide to rest, where Zack has a flashback to his childhood where he lived under abusive caretakers. They then proceed to the next room, where Zack is forced to relive his childhood through a dollhouse puzzle, further angering him. Heading to the next room, they find two syringes that must be used in order to proceed, with one syringe being harmless and the other containing a dangerous drug. Zack decides to inject both syringes into himself and becomes more aggressive as a result of the drug, threatening to kill Rachel. Rachel reminds Zack about their deal and asks if he really wants to kill her, which helps calm Zack down. Not wanting to become a liar, Zack tells Rachel not to let herself get killed by him. (Source: Wikipedia)

扎克注射藥物，在殺意掙扎中警告瑞秋

After willingly shooting a dangerous drug into his arm so that they could move forward, Zack begins to grow overwhelmed by the urge to kill. But with the last traces of rationality left in his mind, he tells Rachel to not let him kill her yet. (Source: Funimation)

Rachel 深入 B2 層，尋找治癒 Zack 自殘傷勢的解藥

After slashing open his own belly, Zack is left without the strength to stand, so Rachel sets off alone into Floor B2 in search of something to stop his bleeding. (Source: Crunchyroll)

Rachel和Gray在Danny的病房為Zack尋找治療方案

Rachel heads to Danny's floor with Gray, the priest, to search for something she can use to treat Zack. However, Gray tells her she must undergo a series of tests to get there. (Source: Crunchyroll)

Danny 帶回涉及 Rachel 眼睛以換取藥物的交易

Danny, who Zack thought he killed on Floor B5, shows up and offers Zack a deal: Rachel`s eyes in exchange for medicine to treat his wound. Meanwhile, Rachel finds Zack`s room on Floor B6 and retrieves the knife he asked for. (Source: Crunchyroll)

Ray 面臨女巫審判，Gray 基於 Danny、Eddie 和 Cathy 的幻覺來審判她。

Ray runs into Gray, who reveals that he has confiscated the medicine Danny was carrying. The scene shifts to a courtroom with Gray presiding as the judge over a witch trial to determine her identity, with the hallucinations of Danny, Eddie and Cathy to testify against her. Cathy points out that Ray is hiding a lying heart under her calm facade, Eddie laments that Ray is selfish, and Danny boasts of her corrupted and unsaveable soul. With all the testimonies against her, Gray declares Ray a witch and sentences her to be burned at the stake. (Source: Wikipedia)

Rachel 送藥給 Zack，Zack 在電梯裡分享故事

Rachel manages to bring Zack the medicine. They get into the elevator and Zack tells Rachel a story.

試圖掌握關於她的一切細節

Zack 就 Ray 的過去及其作為 B1 天使的真正身份向她對質。

Zack continues watching a recording of an interview between Danny and Ray, where Ray reveals that her parents were abusive and hated her and each other. One night, her father finally snapped and stabbed her mother to death, prompting her to take her mother's gun and shoot her father to death. Afterwards, she stitched their bodies together in order to create the "perfect family" and lived happily with them until the police arrived. Noticing her blank, blue eyes, Danny reveals to Ray that his mother committed suicide due to him having been born missing an eye, and he becomes obsessed with Ray since her eyes resemble his mother's. Angry and disgusted, Zack storms back to where Ray and Danny are and proclaims his suspicions that Ray is in fact the "angel" of B1, which Danny confirms, and reveals that Ray was sent to B7 after finding newfound faith in God by reading a Bible. Knowing that she lied to him, Zack angrily declares that he is not Ray's God and asks her if she will kill him, as a trespasser on her floor. Ray flees, luring Zack through more traps until he manages to corner her in the last room. He once again asks her if she intends to kill him when Danny arrives and holds him a gunpoint. Cornered by the two of them, Ray then calmly draws her gun and fires. (Source: Wikipedia)

Ray 和 Zack 在探索建築各層並面對自毀程序時，發誓要殺死對方。

Ray shoots Danny much to his surprise, claiming that Zack is hers to kill and sew up. However, she remains conflicted since she has lost her faith in her God, meaning there is nobody left to forgive her for her crimes, and hesitates in shooting Zack. Pushing her down, Zack reminds Ray that he made the promise to kill her, not her God, shaking Ray back to her senses. The two swear to each other again on their vow and attempt to continue their way out. Although B1 is Ray's floor, she is unaware of its location even after knowing every nook and cranny of the place, deducing that the exit must be on B2 due to her floor being the last to be built and the strange observation that no one ever came down from above. While on the way to reactivate the elevator, she encounters Gray, with questions her intentions and her identity, telling him that she has accepted herself and will hence take responsibility for her own actions and choices from now on. Satisfied with her answer, Gray gives her a hint that the exit is behind the huge stained glass window of his floor. When Zack and Ray reunite, they try to find her gun as well but realize Danny's body is missing once again and that Ray's gun has been destroyed. Together they warily return to B2, where Zack smashes through the stained glass window to reveal a long flight of stairs leading to the surface. Just then, the building's self-destruct sequence is initiated. (Source: Wikipedia)

扎克克服對火的恐懼，掰斷鐵欄；丹尼在誓言討論後射傷雷。

Ray and Zack flee up the stairs as the facility begins to burn and collapse, but their way is blocked by steel bars. Zack briefly has a panic attack due to his fear of fire, but he manages to regain his senses upon seeing Ray struggling to break the bars. Overcoming his fear, Zack manages to break through the bars and all other obstacles, though he breaks his scythe in the process. They finally reach the top floor, where Ray asks Zack if he truly wants to kill her, and she wouldn't fault him if he changed his mind. Zack reaffirms the promise he made when Danny arrives and shoots Ray in the back. He reveals he was the one who activated the self-destruct sequence and holds Zack at gunpoint to watch Ray die, so he will have to live with the knowledge he couldn't fulfill his promise. Ray assures Zack that she doesn't care if their vow is fulfilled or not, only that the vow was made in the first place, and she will carry the burden of their vow so Zack doesn't need to think of himself as a liar. Jealous of Ray's affection for Zack, Danny shoots Ray again and prepares to kill Zack when Gray disables him with a crossbow. Grey orders Zack to leave through the exit, assuring him there is still a chance to save Ray. Zack picks up Ray's body and heads for the door with Danny still pointing his gun at his back. (Source: Wikipedia)

Gray與Danny在倒塌的建築中面臨死亡，Zack和Ray則帶著承諾逃離。

Gray shoots Danny again to prevent him from shooting Zack. As Zack carries Ray through the exit, Gray has a final conversation with Danny, revealing that he became fascinated with how Ray and Zack managed to change each other, and how he's come to realize that everybody is a human, both flawed and beautiful. The building then collapses, presumably killing both Danny and Gray. Zack is able to reach the surface just as the police arrive to investigate the building collapse, surrendering to the police so Ray can be taken to a hospital. After recovering from her wounds, Ray is taken to a mental care facility where the staff attempt to rehabilitate her with limited success. Deemed guilty for his murder spree as well as killing Ray's parents and kidnapping her, Ray is informed that Zack is sentenced to death. However, shortly after hearing the news, Zack breaks into Ray's room to fulfil their oath, having escaped prison. As they both leap out of the window to escape, Ray once again pleads for Zack to kill her, which Zack reaffirms by telling her to stop crying and smile. By the time the police arrive, the room is already empty with a splatter of blood on the windowsill and Zack's knife on the floor. (Source: Wikipedia)