The Shie Hassaikai Raid also known as the Hassaikai Incident is a Police Raid where the Hero Agencies of Sir Nighteye, Fat Gum, and Ryukyu combined with other Pro Heroes and the Police Force to seize the Shie Hassaikai Compound to rescue Eri and arrest Overhaul.
Sir Nighteye and his office near the climax of their investigation against Overhaul and the Shie Hassaikai. They invite Fat Gum's office, Ryukyu's office, Shota Aizawa, Rock Lock, and Gran Torino among other Pro Heroes. The hero offices also allow the U.A. High School students to participate.
Since the incident when Overhaul attacked Team Reservoir Dogs, the Heroes at the Nighteye Agency have been investigating the Shie Hassaikai. Centipeder notes that the Yakuza organization has been making contact with several other parties and appears to be gearing toward accumulating funds for an unknown operation. Centipeder and the Police Force confirmed that Overhaul made contact with the League of Villains and that a fight occurred.
The Nighteye Agency recruited Gran Torino and Naomasa Tsukauchi because they're investigating the league. Sir Nighteye also invited heroes who have experience dealing with criminals who are active on the Black Market. Fat Gum reveals to the group that the Shie Hassaikai are distributing bullets that have the ability to erase Quirks. Unlike Shota's Erasure ability, these bullets have the potential to damage a person's Quirk Factor.
Tamaki Amajiki's injuries from the previous battle healed and his Quirk returned, but this drug still holds dangerous potential. Fat Gum explains that research involving one of the confiscated bullets contained blood and human cells. This means that this drug derives from someone else's Quirk. The Shie Hassaikai are likely using middlemen organizations to deal the bullets just like they do for Trigger.
Sir Nighteye reveals that Kai Chisaki is the Yakuza Captain of the Shie Hassaikai and his Quirk ability is called Overhaul. He says that the Shie Hassaikai are armed with Quirk-Destroying Bullets and a Quirk that can disassemble and reassemble anything. The villain group has likely been distributing the test samples to gain the interest of other criminals. Sir Nighteye believes that the Quirk-Destroying Drug is made from Eri, a girl who Izuku Midoriya and Mirio Togata encountered during their Work-Study. The upcoming operation to raid the Shie Hassaikai's hideout is aimed at rescuing Eri.
The Nighteye Office worked hard to gather information about the Shie Hassaikai's circle of connections and triangulated areas where Eri might be. The heroes gathered at this meeting are tasked with searching these places for the hideout and Eri.  The mission begins a few days later after Sir Nighteye tracks a member of the Shie Hassaikai to a toy store where he was getting presents for Eri. Bubble Girl and Centipeder were able to successfully stakeout the correct hideout and discover the proper time frame when Eri and Kai will be there.
|League of Villains|
Just as the Police prepare to enter the large residence, Rikiya Katsukame bursts through the door with a giant right hook. Two men get flown high into the air but Deku and Eraser Head are able to secure them. Rikiya is surprised the Heroes got wind of the Shie Hassaikai's themes. He attacks but is met with Ryukyu's powerful dragon-shifting Quirk. Team Ryukyu engages the giant villain while the others storm the base.
The heroes are met with a large resistance of yakuza thugs. The smaller time heroes subdue them after a battle of Quirks. Overhaul senses the heroes fast approaching and assigns his Eight Bullets to deal with them.
Sir Nighteye leads the group to Overhaul's secret escape passageway he learned of using his Foresight. Yakuza thugs ambush the Heroes, prompting Centipeder and Bubble Girl to retaliate. Centipeder uses his Centicoil technique and Bubble Girl uses her Bubble Quirk to subdue the criminals quickly. The heroes run down the stairs into an underground labyrinth that has been warped by Overhaul's Quirk.
Lemillion slips through a distorted wall and confirms they haven't run into a dead end. Deku and Red Riot use their Shoot Style and Red Gauntlet Super Moves to break down the wall and open the path. However, the path has been warped and distorted by yet another Quirk. This time, it's Mimic of the Shie Hassaikai using his Mimicry Quirk to merge with the path and warp it. Tamaki starts to panic about being unable to continue on but Mirio reassures him and goes ahead by phasing through the path.
Mimic drops the rest of the group one floor below where Toya Setsuno, Yu Hojo & Soramitsu Tabe are waiting to ambush them. Suneater realizes the villains are trying to buy Overhaul time and resolves to face the villains alone while the others go ahead. Eijiro pleads with Tamaki to fight with the team and then the villain's attack. They pull out weapons after having their Quirks stolen from them by Eraser Head. The Police pull out their firearms and panic, but Suneater swoops in and defuses the situation. He ties up the criminal trial and asks the others to go on without him.
Suneater allows the others to continue the mission while he fights Toya, Yu, and Soramitsu alone. Suneater controls the fight early but Toya and Yu push back when their Quirks return. Suneater stays strong by going past his limit and using his Super Move: Chimera Kraken. Soramitsu wakes up having been knocked out by Eraser Head and turns the tide of the fight into the villain's favor. Suneater channels inspiration from Mirio's dedication and makes a comeback victory over the trio of expendable bullets.
Mimic slows down the Police mob on the upper floors, allowing Nighteye and Fat Gum's squads to traverse further into the labyrinth. Mimic notices that Toya, Yu, and Soramitsu have been defeated and is surprised because they had considerable abilities as a team. He turns his attention to Eraser Head and attacks him using the walls of the tunnel. Fat Gum and Red Riot save him and end up tumbling down a hole to another room where Kendo Rappa and Hekiji Tengai await them.
Kendo makes the first move and crushes Red Riot's Super Move. Fat Gum stands up to the fearsome Spear and Shield combo while Eijiro combats his fears.  Eijiro feels helpless as Fat Gum and Kendo engage in a slugfest, fearing that he's powerless to help. Fat Gum has his own tricks to counter the villains but needs more time to carry it out. Eijiro fills the role of a Spear and attacks Kendo on his own. Thanks to Eijiro's manly sacrifice, Fat Gum gains the power to win the brawl of spears and shields.
Mimic turns his attention back to Nighteye's group and tries to crush them using the cave walls. Rock Lock's Quirk keeps an area around the team stable, allowing them to traverse slowly forward. Mimic's Quirk is putting great strain on his body and didn't use this type of attack until he felt he had no other choice. Mimic changes the shape of the cave to let in a temporary squad created from members of the League of Villains: Himiko Toga & Twice.
Himiko injures Rock Lock and Twice attacks Sir Nighteye and the Police using a clone of Kendo. Nighteye makes short work of the clone and forces Twice to retreat. Himiko and Twice regroup and decide they're free to act on their own. Himiko and Twice use the heroes to their advantage, giving away Mimic's position in the walls by taunting him to the point of a temper tantrum. Deku and Eraser Head defeat Mimic and the League members escape, satisfied with themselves.
Lemillion manages to catch up with Overhaul and Chronostasis before they escape. Shin Nemoto and Deidoro Sakaki ambush him while the villains take Eri away. Lemillion manages to avoid all of Shin's Quirk-Destroying Bullets and finds his resolve despite the villain's constant verbal abuse. He defeats both the villains instantly using his Super Move: Phantom Menace.
Mirio quickly catches up to Overhaul and attacks. He swipes Overhaul away and phases his foot through Eri's face to knock Chronostasis away as well. Lemillion takes Eri into his arms and promises to be her hero. Overhaul activates his Quirk and attacks Lemillion and Eri. He claims he can restore Eri's body to normal whenever he wants and he's sealed off any means of escape. Chrono threatens to destroy Mirio's Quirk with the Quirk-Destroying Bullets loaded into his pistol.
Lemillion evades all of Chrono's shots and wraps Eri in his cape. He disarms Chrono and launches a fierce counterattack that proves he's stronger than even Overhaul. Eri watches inspired that she might actually have a hero. Shin craws his way into the cave and Overhaul commands him to shoot Lemillion.
Shin aims the bullet at Eri, knowing that Lemillion will give in to his heroic nature. Mirio jumps in front of the path of the bullet and sacrifices his Quirk to protect Eri. He promises the young girl that she'll never have to know pain again.
Overhaul taunts Mirio's efforts, only to get beat down by a Quirkless Hero who proudly claims he will always be Lemillion no matter what. Mirio fights another third of the battle without his Quirk, protecting Eri the entire time. Before Overhaul can kill Mirio, Deku and Team Nighteye burst onto the scene.
Deku, Eraser Head, and Sir Nighteye left the Police to pursue the League of Villains. Injured, Rock Lock stays behind with Mimic. The rest of Nighteye's Squad confronts Overhaul and Eraser Head takes his Quirk. Deku attacks and Overhaul is forced to wake an unconscious Chrono. Chronostasis wakes up and uses his Quirk to take Eraser Head out of the fight. Overhaul's Quirk returns to him and sacrifices Shin to fuse them together.
Overhaul reveals Lemillion lost his Quirk forever and Deku tries to hold Overhaul's monstrous new form back. Sir Nighteye switches places with Deku and confronts Overhaul about fearing Lemillion's power. They engage in combat while Deku tries to escort Eri and Mirio out of the cave. Nighteye sees into Overhaul's future and has a vision of him winning and fleeing with Eri. Sir Nighteye goes past his limit and Overhaul grievously injures him. Deku rushes back into the fight, determined to defy fate.
Deku uses 20% of One For All to combat Overhaul's second form. Despite his enhanced power, Deku proves no match for the villain and gets injured. Eri rushes out to save Deku by sacrificing herself. Before Overhaul can make a move, Ryukyu's team comes crashing through the ceiling with Rikiya. Himiko and Twice lead the Heroes to the underground cave in an attempt to defy Overhaul. Overhaul captures Eri and tries to escape through the newly formed hole in the ceiling.
Eri notices Lemillion's cape and is inspired to act so she can save everyone. She awakens her power and rewinds Overhaul back to his normal human form. Eri jumps into Deku's arms and they stand up to Overhaul together. Deku keeps Overhaul away from Eri and accidentally goes over his limit for One For All. However, he doesn't injure himself. Overhaul merges himself with Katsukame while Ryukyu's team tends to Sir Nighteye.
Deku realizes that Eri's Quirk can rewind any injuries he sustains while using One For All. Eri's Quirk is the ability to rewind anyone to a previous state. Deku asks that Eri lend her power to him while he accumulates enough injury to avoid getting rewinded to death. Determined to end the conflict once and for all, Deku unleashes One For All: Full Cowl - 100%!
Overhaul makes his last stand and uses his new kaiju-like form to attack Deku. In spite of his titanic power, Overhaul is easily overpowered by Deku running at 100% of One For All's power. With incredible speed, Deku can exploit Overhaul's recovery time. He barrages Overhaul with a rain of punches all firing at 100%. He finishes Overhaul with a punch that never appeared in Sir Nighteye's vision. Deku defeats Overhaul with a fist that opens the future.
Overhaul attacks one last time but Eri's power explodes and rewinds him back to normal. She's unable to control her power and it spirals out of control until Eraser Head cancels out her Quirk and Deku's. They both fall unconscious, victorious at last. The mission ends at 9:15 AM the next morning.
Following Overhaul's defeat, the Heroes and the Police finish the sweep of the headquarters and arrest all eleven members of the Shie Hassaikai. The villains are transported to a Villain hospital. Eijiro, Eri and Sir Nighteye are brought to a hospital as well. Before he's carried away, Sir Nighteye tells Deku that he managed to twist the future.
The Police take the villains away via the highway. They confiscate their belongings and the Quirk-Destroying Bullets. On their way to the hospital, Tomura Shigaraki and the League of Villains ambush the transport escorting Kai. Dabi stops the Police escort with a flaming attack that gets intercepted by the Sand Hero: Snatch.
Snatch holds off the League of Villains until Dabi and Mr. Compress kill him. Tomura takes out the remaining Policemen and takes Kai out of the transport. He and Compress remove both of Kai's arms and steal the Quirk-Destroying Bullets. Tomura adds insult to injury and mocks Kai's life's work before the League of Villains makes a dramatic exit.
The incident resulted in four destroyed homes and three injured civilians. All Heroes who received injuries are admitted into the hospital. Nejire Chan and the others remain behind to clean up the incident and aid the injured.
Deku doesn't receive treatment for anything other than light wounds and Shota gets a few stitches. Rock Lock doesn't suffer any internal damage and Fat Gum's team is expected to make full recoveries. Eri enters a fever state and is quarantined inside the building.
All Might and Recovery Girl visit Sir Nighteye on his Death Bed alongside Bubble Girl and Centipeder. Deku joins them and eventually, Mirio does as well. Sir Nighteye says his final goodbyes to his pupils and his hero All Might.