The New Captain of the 3rd Division

 is the beginning of the Kasumiōji Conspiracy. It details the first mission the Third Division is entrusted with, shortly after the introduction of Shūsuke Amagai as Captain.

Prelude
10th Division Lieutenant Rangiku Matsumoto announces to her captain that there is going to be a new captain for the 3rd Division, but he states that he was already notified. Rangiku wonders when Kira mastered Bankai, but Hitsugaya states that he wasn't the one becoming captain, much to Rangiku's surprise. Meanwhile, Captain-Commander Genryūsai Shigekuni Yamamoto announces that he has approved of the new captain for the 3rd Division, Shūsuke Amagai, as he enters the captain's meeting. The 3rd Division's forces are skeptical of letting a nobody become the captain of their division.

The New 3rd Division Captain
As Amagai strides down towards the Captain-Commander, the other Captains watch him intently, as he introduces himself. After the meeting, Captain Jūshirō Ukitake confides with Amagai, telling Amagai that if he is uncertain of anything, to come to him. Captain Sajin Komamura asks Captain Shunsui Kyōraku who were the other captains that oversaw the examination, but he reassures his fellow captain, stating that they've now got one less vacant position. Captain Suì-Fēng approaches them, stating that Amagai has to prove his worth to the Gotei 13.

Amagai then approaches the 3rd Division and its Lieutenant, Izuru Kira. He introduces himself immediately, as well as his ally from the Patrol Corps, Makoto Kibune, who he states to be the 3rd Seat. Another member approaches Amagai, stating that the 3rd Division has been fine without a captain until now. Amagai agrees with his resentment over the issue, stating that he himself would be annoyed if someone he had never met before was announced as a captain for his division. However, he reassures the division members, saying that he will protect them so long as he is their captain. Afterwards, Rangiku is seen talking to Kira, stating that there is no way to determine the new captain’s capabilities. He then reveals to Rangiku that no one in the division trusts Amagai, and they have a bad attitude towards him. He then looks despondently into his cup, staring at his reflection. Rangiku realizes that he is nervous, and gives him a bottle of sake to ease his worries. But before he can drink any, Captain Tōshirō Hitsugaya intervenes, berating his lieutenant for hiding sake bottles inside the cabinet.

Meanwhile, at the 3rd Division barracks, Amagai and Kibune come across a welcoming party for the two new members. Amagai thanks the members of his Division, but it is clear that they still don’t entirely trust him yet. Kira gives his captain a cup of sake, to which he reluctantly takes. He glances down at the cup, whilst Kira comments upon the tense nature of the party. Kira breaks the silence abruptly, requesting a toast for Captain Amagai, who greets the masses of 3rd Division members before him, and drinks the sake, as Kira comments on his drinking ability. Suddenly, Amagai’s cheeks flush red, as it is inherent that he is drunk. The other division members watch on, as he collapses. Kira jumps to his aid, as he tries to wake Amagai up, but Kibune states that the Captain has a weakness for liquor. he then goes on to say that he drank the sake out of respect for Kira and the other members of the 3rd Division. Kira wonders whether to cancel the party due to Amagai's condition, but Kibune states that they should use this opportunity to familiarize themselves with each other.

Kyōraku is seen relaxing on top of a building, and is approached by his lieutenant, Nanao Ise. Kyōraku notices that the 3rd Division is having a party to commemorate the ascension of Shūsuke Amagai to the mantle of the 3rd Division captain. Kyōraku wonders out loud whether he and Amagai will become friends, and Nanao states that she wouldn't know, to which he comments upon his lieutenant's cold nature. Meanwhile, Amagai is seen being fanned by another division member, as the party continues undeterred. Kibune is seen writing down the names of all the division members in his notebook. As Kibune leaves the 3rd Division barracks, it becomes apparent that the other members are unwilling to acknowledge Amagai as their captain. Meanwhile, Kira is seen by himself, and is approached by Kibune, who reassures Kira, stating that it has been he who has kept the Division in order since his Captain defected, but Kira denies this, saying it was no big task. But before they can continue talking, an emergency message is relayed by the Hell Butterflies, outlining that several Menos Grande have appeared in the Dangai and are heading towards Soul Society.

Third Division Goes to War
The Shinigami Research and Development Institute identifies that there are approximately 30 Menos present in the Dangai, much to the surprise of several Captains. Yamamoto orders the Gotei 13 to mobilize and prepare for the arrival of the Menos, with the 3rd Division being given the task to eliminate the Menos. At the 3rd Division barracks, Amagai is still recuperating from his ailment, and Kibune asks Kira to lead the Division into the Dangai, stating that he will ask for the Seizing Currents to be shut down. Kira assembles the 3rd Division in front of the Senkaimon, organizing them into platoons of four per enemy, and he warns them to be on guard, as they are up against Menos Grande. The 3rd Division then charges through the Senkaimon and into the Dangai. As the 3rd Division plunges into the Dangai, they soon come across several Menos, who are around the same height of the opposing mountains. Kira orders the platoons to split up, as he takes on the Menos nearest to himself, by releasing his Zanpakutō, Wabisuke, which easily eviscerates the Hollow. The other members charge at the Menos, easily disposing of them in their organized four-man platoons.

The Shinigami Research and Development Institute reports that five of the thirty Menos have been exterminated, but before Rin Tsubokura can say anymore, an alarm blares. As the 3rd Division continues its fight against the Menos, Kira urges them to continue fighting, as a rumbling sound reverberates throughout the Dangai, indicating that the Seizing Currents have been reactivated. The Shinigami wonder why the currents have reactivated, but before they can do anything, a pulsating yellow dot appears from afar. As it nears them, they realize that the Cleaner has also been reactivated. However, Rin is unable to divert the path of the Cleaner as it proceeds steadily towards the surprised members of the 3rd Division, knocking over several Menos in its wake. Kibune appears, stating that he is unsure of why the Seizing Currents have reactivated. Kira orders the retreat of the 3rd Division members, as several Menos attempt to stop their progress. One fires a Cero, which is deftly blocked by Kibune, who deals the Hollow a killing blow to its center.

After Kibune kills the Hollow, he takes up the rear to ensure that all of the 3rd Division's members make it out alive. However, they underestimated the speed of the Cleaner, as it nears closer towards them. However, Amagai intervenes, jumping between the 3rd Division and the rapidly advancing Cleaner. The members of the Division watch in awe as he stands, unwavering in front of the massive Cleaner. Kira attempts to stop him, but Amagai says it is his duty to protect his subordinates. Kira looks to Kibune, who nods, telling him to observe the true strength of Captain Amagai. As the Cleaner nears him, Amagai thrusts a unique weapon he carries upwards, with green Reiatsu spilling outwards from the point of impact, causing the Cleaner to disintegrate. Amagai retracts his unusually shaped weapon, cleaning it with a cloth, throwing the papers over his head, as he stares back at Kira. Amagai asks his Kibune whether he was absolutely sure that he ordered for the Seizing Currents to be shut down, and states the dubious nature of this act. He dismisses this, turning his attention to the other members, asking if they are injured.

Aftermath
He commends Kira on keeping a level head, even without his Captain's presence, and states that is what he would expect from someone who was able to lead his Division without a captain. The other members realize that he isn't just an ordinary captain. Amagai falters, which causes them to look up at him, as he collapses onto the ground. Kira and Kibune run over to him, and comment upon the rash nature of his action, as he subdued the Cleaner whilst he was drunk. Kibune lifts him up, and they proceed to leave the Dangai. He turns to Kira, stating that they ought to leave and return to Soul Society.