— Technological Development Bureau
The Institute is heavily damaged. The 4th Squad has arrived to take care of the injured researchers. The Szayelaporro-lookalike is nowhere to be seen. Mayuri's trial has been put on hold. He and Nemu (he had taken her with him to the trial) are back at the Institute. Mayuri is talking to Akon. Akon apologies for the damage, but Mayuri just wants answers. And why didn't the enemy finish them off? Akon answers it's because the lookalike had a strange reaction when he found the specimen.
— 30 minutes earlier
All the researchers had survived the arrancar's attack. He praises them. Seems they weren't as non-combatant as he had assumed. He'll be sure to study their corpses later. But he has something else to take care of first. The male intruder walks towards a pillar-shaped tank. The specimen which he's looking for is floating in a luminous fluid inside it. Usually, when an arrancar dies after being cut with a zanpakutô, its soul is purified and its body disappears. Mayuri made a special device to prevent this, allowing him to preserve his specimens. The man laughs when he finally gets a look at the specimen, "Hahaha, this matches the recording spirit-bugs' data. A dumb look on my face, not even realising my own death." He turns back to the researchers and says, "Rejoice. You get the rare chance to see the re-fusion of a soul and body that died once." Then he dips his hand in the liquid and touches the specimen.
Nothing happens. He curses Mayuri — he must've done something. He reaches for his sword, ready to take his anger out on the researchers, but stops. He senses the spiritual-pressure of the man who cut Nnoitora and Yammy. He doesn't want to take that beast on in his current condition. The intruder blends into the air and disappears, along with the specimen. At the same time there's a thunderous noise.
— Present time
Having heard Akon's retelling of the events, Mayuri grinds his teeth, "In other words… Captain ZARAKI is the one who destroyed the wall…" The 11th Squad had supposed to be near the gates. However, ZARAKI had probably gotten lost again, had seen the explosion and had headed towards the Institute. Mayuri asks if the arrancar blended into the air in the same way as the masked woman in Karakura Town. Akon says that, judging by the footage on the woman, it's the same. Akon asks if Mayuri knows "what" the intruder was. Mayuri says he can make a guess, but… — "I hope my guess is wrong, though."
— Soul Society, somewhere in Seireitei
Shunsui KYÔRAKU sees her standing near the little retreat where Jûshirô UKITAKE, the 13th Squad's Captain who suffers from a lung disease, tends to rest. UKITAKE hadn't attended the emergency captain meeting due to his health. KYÔRAKU planned to check up on him, and, if possibly, to discuss things. Commander YAMAMOTO had informed the attendees that they were now permitted to use their full powers and to carry their zanpakutô at all times. A white skull covered the right side of her face. An arrancar. KYÔRAKU lowers his spiritual-pressure as low as he can to remain unnoticed. He decides to wait and see what she'll do. KYÔRAKU feels both curious and cautious at how quiet her spiritual-pressure is. Everything in Soul Society is made up of spiritualmatter. Hers was as quiet as that of a stone lantern or a tree.
— "Are you lost, miss?" She turns to him in surprise, and at the same time, the kind of spiritual-pressure which you'd normally expect of an arrancar, does rise up now. — "You are… You are the person who was with Kenpachi KURUYASHIKI-san back then, aren't you?" Her words surprise KYÔRAKU. She starts to melt into the air. — "I… I'm sorry. The scenery was just so beautiful that I unintentionally connected to it. I'll disappear now, so please don't mind me." Why does she know KURUYASHIKI? However, the woman is already gone before he can ask her. UKITAKE pushes the bamboo screen in front of his retreat to the side and calls out to KYÔRAKU, "KYÔRAKU? What's wrong? I thought I sensed an arrancar for a second…" KYÔRAKU says it's nothing. And he really hopes it's nothing, but he has a bad feeling. Not because of the name Kenpachi KURUYASHIKI, but because he remembers the man who had killed KURUYASHIKI.
— North Seireitei, Black Ridge Gate
A few Picarro and soul reaper are in battle near the Black Ridge gate. The soul reaper are suspicious of how quickly these arrancars seem to heal. They do go down when cut, but then stand up again as if nothing happened after a short while. The Picarro suddenly stop fighting. They notice that there are suddenly a lot less "threads" inside the walls. The masked lady must've left. Some Picarro want to continue "playing" with the soul reaper, but the head-phoned Picarro reminds them of their race against Don
KANONJI and they use sonído to leave. Meanwhile, the soul reaper receive word that ZARAKI is heading towards them to engage the enemy. But the enemy is already gone… ZARAKI isn't going to be happy.
— Underground Prison, lowest level, 8th prison: Muken
Darkness. Everywhere. Making you lose sense for what's left, right, up or down. That is the prison called Muken. There were only a few prisoners in Muken, but even so, Soul Society preserved this space at all costs. To make its criminals unable to feel "the world". And, at the same time, to hide its criminals from "the world". To make them be forgotten. To make them into beings which "didn't exist". There was barely anyone in Soul Society who knew who the Muken's first prisoner was, and whether that person still existed. But many knew its latest prisoner.
Sôsuke AIZEN. A soul reaper, yet king of the hollows. The traitor who tried to attack the Soul King. Immortal thanks to the power of the hôgyoku. And now imprisoned in Muken. His limbs, eyes, ears, mouth, the feeling of touch — everything had been bound and sealed. But a part of his senses was suddenly freed. Part of the cloth covering his face was peeled off, freeing one eye, one ear and his mouth. His freed eye saw darkness. But not pure darkness. In this place where there should be no light, there was a lantern burning brightly in front of his chair. There was also a man standing next to the lantern. Neither of these things seemed to surprise AIZEN. And while a normal person would've needed several hours to regain the ability to speak properly after being sealed for over a year, AIZEN spoke calmly, — "Should I be honoured to lay my eyes on such a senior prisoner? What should I call you? Your real name, Sôya AZASHIRO? Or the title given to the strongest soul reaper in Soul Society? The 8th Captain of the 11th Squad… Kenpachi AZASHIRO."
The woman standing behind AZASHIRO finds AIZEN's calmness hilarious. She suggests taking the hôgyoku from him. AZASHIRO tells the woman to stay quiet. AZASHIRO tells AIZEN that he has no interest in the hôgyoku, nor in AIZEN's crimes. He simply wants to ask about "the outside". AIZEN asks why, — "You can see through all of Seireitei, even while being in Muken. You're a man on who even my Kyôka Suigetsu's illusions will likely not work. What could I possibly tell you?" AZASHIRO remains silent, but the women laugh, saying it took AZASHIRO two days to see through Kyôka Suigetsu's illusion. He had muttered, "something is strange", the entire time. He silences her again. He says he wants to know about outside of Seireitei. And he also wants to ask about AIZEN's defeat. He hadn't expected him to lose against Ichigo KUROSAKI. The woman interrupts again. She says AZASHIRO had predicted AIZEN would be stopped by the Zero Squad. But it never even got to that point. Is he embarrassed he got it wrong?
— "My defeat? If I look back on how disordered my heart was back then, I can say that defeat was a meaningful experience. You should experience it once." AZASHIRO disagrees with AIZEN's words. He sees no merit in experiencing defeat. But they will discuss it no further since he has no interest in meaningless chatter. AIZEN says he'll answer AZASHIRO's questions. AZASHIRO thanks him. After all, this serves no merit to AIZEN. AIZEN disagrees, — "On the contrary, predicting your actions and its outcome based on your questions will serve as a nice way to kill time." Having gotten answers to all his questions, AZASHIRO disappears by melting into the air. In the same way the masked woman and the Szayelaporro-lookalike had done. AIZEN closes his eyes with a faint smile on his face, imagining the outcome of AZASHIRO's actions. The Muken returns to being a place of absolute darkness once again.