K: Return of Kings

A year has passed since the School Island incident, where four of the seven kings fought for their lives to stop the evil Colorless King. Since then, Silver King Yashiro Isana has gone missing and the Green Clan JUNGLE has become more active in spreading their influence over the community, much to the annoyance of Blue Clan SCEPTER 4 and Red Clan HOMRA.

Hoping to learn more about his recent encounter with JUNGLE, Blue King Reisi Munakata summons Kuro to SCEPTER 4; Neko waits at HOMRA's home base for her partner.

In a flashback, Mikoto surrenders to Reisi rather than fight him. As Reisi interrogates Mikoto, he wonders why the Red King has yet to choose his successor. Meanwhile Shiro asks Kuroh who were the people with powers chasing him and the "Kings". Kuroh reveals Japan is secretly being ruled by seven psychic clans called the Seven clans of Color, each ruled by a King. Unlike the Red Clan Homura and Blue Clan Scepter 4, whose clans posses the power of fire and ice respectively, his late master's clan, the Colorless Clan, have the power of premonition. Before his master, Ichigen Miwa passed away, he had a vision that his successor, Shiro, might become evil, which Kuroh is tasked to kill him if there is proof. Shiro convinces Kuroh the video released by Homura might be a fake and he shouldn't use that to quickly judge him that he is evil without knowing him first. Kuroh agrees to stop attacking him and get know to Shiro but if he ever turns evil, he will kill him.

Shiro desperately tries to find a possible alibi in order to prove to Kuroh he was not there during the time of the video. Meanwhile, Homura and Scepter 4 are able to close in on Shiro's whereabouts. Thanks to Kukuri who is able to provide proof that Shiro was with her during the time of the shooting, Shiro and his friends prepare for the school festival. When he goes to his dorm and opens his closet, he is shocked to discover a bloody school uniform that matches the murderer's picture which leads Shiro to rethink the whole situation. As he contemplates, Yata and Kamamoto arrives at Ashinaka.

Shiro, Neko and Kuroh heads to the city to buy more fireworks for the festival. Meanwhile Seri and Saruhiko arrives at Ashinaka and orders the principal to give them all their information on Shiro, unaware he had just left. While Saruhiko illegally access the student council's computer to find Shiro in the student database, Misaki and Rikio asks the students for information about Shiro but due to their looks and Misaki's temper, they only scared them. Saruhiko soon encounters Misaki and Rikio, where he mocks and insults his former friends which angers Misaki to fight him. The fight is soon stopped by Seri who orders Saruhiko to returned to Scepter 4 as neither the school or it's database has a record of Shiro being a student at Ashinaka. When Misaki asks a female student about Shiro before leaving, the student, Kukuri tells him she has no idea who Shiro is.

Shiro begins to question his own identity after realizing there is an inconsistency between what he remembers and what actually happened. Meanwhile, Lieutenant Seri Awashima of SCEPTER 4 makes a visit to the bar owned by Izumo Kusanagi.

Scepter 4 has finally tracked down Shiro as they prepare to arrest him. Neko creates an illusion in order for Shiro to escape, but is easily thwarted by Reisi who reveals that she has the power to manipulate people's minds by giving them false memories. While Kuro fights Reisi, Neko escapes with Shiro. When Kuro is nearly defeated, Shiro appears and reveals his true identity to them as the new Colorless King, using his power to let him, Kuro, and Neko escape. After they get away, Shiro convinces Neko to undo the amnesia spell on him to find out the truth.

Shiro finds out from his recovered memory about being involved with the Silver King. He contacts Reisi about his findings, while the rest of Scepter 4 tracks his location. When they reach the location they find out that the phone call was rigged by Shiro. Meanwhile, Reisi send his forces towards the Silver King's airship to take him into custody, unaware that Shiro, Kuroh, and Neko are secretly on a plane also heading to the ship, but as they approach, the Silver King sets off an explosion.

In the year 1945 at Dresden, Germany, Adolf and his older sister experiment a relic called the Slate that gives people magical powers. During a bombing raid, Adolf's sister is killed but he himself survives thanks to the power of the Slate. Distraught over her death, Adolf leaves Germany and brings the Slate into his airship Himmelreich. Back in the present, Reisi visits the Golden King, Daikaku Kokujōji, wanting to confirm if the immortal Adolf is really dead. Believing Adolf is faking his death, Reisi orders Scepter 4 to keep on eye on him. Meanwhile, a mysterious man calls Mikoto from Ashinaka where he mocks him and claims he killed Tatara. Angered, Mikoto breaks out of prison and overpowers Scepter 4. Reuniting with the rest of Homra, Mikoto and gang heads to Ashinaka.

Homra takes over Ashinaka campus as they search for Shiro, Totsuka's killer. Scepter 4 also arrives and are ordered to stand by before they attack. Reisi confronts Mikoto, telling him his actions have gone too far. Reisi is willing to forgive Homra if they leave the campus and Scepter 4 will hunt down and punish Shiro for them but Mikoto refuses. Reisi warns Mikto if he kills Shiro, a King, he will lose control of his powers. Meanwhile, Shiro, Kuroh, and Neko manages to sneak into campus and decides to rescue their friends.

After a confrontation between the Blue and Red Kings, Homra and Scepter 4 forces begin to clash. Mikoto goes off on his own to hunt down Shiro where he eventually finds him with Neko, Kukuri, and Kuroh. During the struggle between Mikoto and Kuroh, Reisi intervenes and strikes at Mikoto. Shiro, Kuroh, Neko, and Kukuri make the chance to escape when all of a sudden, Kukuri stabs Shiro. It is revealed that she is possessed by a White Fox spirit out to target Shiro. The possessed Kukuri escapes while Shiro begins to remember his memories and awakens as Adolf K. Weismann, the Silver King.

Shiro, with his recovered memories as the Silver King reveals that his current body was once possessed by the new Colorless King (White Spirit Fox) who wanted to take over his original body to gain his power, but to no avail instead just possessing his body and not his powers. At that moment, his spirit had jumped to the Colorless King's recent body where he got amnesia. He uses his power to let the students of Ashinaka escape, at the same time cooperating with Kusanagi and Awashima to stop the two clansmen from fighting. Shiro asks Neko to become his first clansmen, and uses her power to find the Colorless King. After she successfully locates him, she passes out and Shiro leaves to confront the Colorless King.

Reisi and Mikoto continue their fight while Shiro tries to catch the Colorless King who's still in Kukuri's body. Helped by Kuro, who becomes his clansman, Shiro tricks the Colorless King to get out from Kukuri's body and trap him into his own body. Shiro teleports to where Mikoto and Reisi are and tells Mikoto to kill him while the Colorless King is still trapped in his body as only a king can slay another king. Mikoto does so, finally avenging Tatara's death but his Weismann level reaches its limit, which his Sword of Damocles is about to crash into the campus. Reisi is forced to kill Mikoto to prevent that which the latter shares some words with his fellow king before passing away peacefully. The Homra gang honors their late leader with a battle cry as they lose their powers. Neko and Kuroh escape the island, still believing Shiro is still alive.