Tale of the Lost Agent

The Tale of the Lost Agent was a major conflict detailing Ichigo Kurosaki seventeen months after Aizen's defeat, completely devoid of any spiritual power or awareness at all. Following his friend's attack, Ichigo decides to regain his lost Shinigami powers.

The conflict began with Ichigo seeking out a mysterious organization called Xcution, who agree to help him regain his powers. As he undergoes training, he encounters a Fullbringer and former Xcution member: Shūkurō Tsukishima.

The conflict concludes following Kūgo Ginjō’s surprising betrayal and the subsequent arrival of the Gotei 13, who restore Ichigo’s Shinigami powers. Shinigami and Fullbringers clash while a personal fight between Ichigo, Uryū, and Ginjō ensures. Ginjō is eventually defeated and Ichigo, despite the startling truths that he's learned, returns to being a Substitute Shinigami.

Prelude
While walking home from school, Ichigo, now seventeen, stops a thief and retrieves the stolen backpack. He returns the item back to its rightful owner: a man who possesses a Substitute Shinigami badge like Ichigo.

The next day after defeating a gang of thugs, Ichigo’s boss Ikumi Unagiya captures him and takes him back to her shop so that he can get back to work. A man, the same one whom Ichigo met just the other day, then arrives. Orihime meets with Uryū and she learns about what had happened to Ichigo. When she leaves, Uryū notes how Ichigo’s beginning to exert reiatsu. The unnamed man that Ichigo met says how he’s looking for people to handle a “troublesome task” for him and requests that they do a background check on Isshin Kurosaki. Ikumi says that she’ll consider it and asks that he leaves, to which he does but not before suggesting that Ichigo should visit Urahara Shop. Ichigo goes there and sees Karin exiting the shop, done with her shopping. The unnamed man returns and warns Ichigo to remain cautious of the people he knows. He introduces himself as Kūgo Ginjō and hands Ichigo a card.

Uryū decides to inspect any strange circumstances around town. He then notices a tall man walking on the rooftop and chases him, but ends up severely wounded. He is brought to the hospital by an ambulance where his father performs surgery on him. Ichigo is told what had happened and he rushes to Karakura Hospital, finding Orihime also there. Ichigo asks about what happened but does not receive an answer. While walking home, he calls a dial using a number on the card Ginjō gave him. A speaker answers and welcomes him to Xcution.

Ichigo manages to contact Ginjō. After they talk, he is given directions for when and where they should meet. The following day, he arrives at the designated meeting place early and sees Ginjō already there. Ichigo says his friend was attacked and that he wants Ginjō’s help, regardless of whether or not he should trust him. They enter the Xcution hideout nearby where three other members await. Ginjō tells Ichigo that their group aims to restore his Shinigami powers and explains about the existence of Fullbringers. His fellow Xcution member and Fullbringer Riruka Dokugamine enters the building with Sado. Ichigo is surprised and angered at Sado’s arrival, but Ginjō manages to calm down. Afterwards, he explains why Xcution wants to restore Ichigo’s powers and Sado, revealed to be a Fullbringer, explains his involvement in the matter. Ichigo decides to help Xcution and regain his powers.

Early Stages
He arrives the next day to begin his training. Riruka uses her Fullbring to miniaturize and place Ichigo in a doll house so that he can fight the doll inside. Ichigo does as he’s told but didn’t defeat Mr. Pork within the fifteen minute time-limit, causing the doll to undergo a drastic power change. Struggling further, Ichigo thinks back to a memory with Rukia and his Substitute Shinigami badge starts releasing black energy in the shape of a swastika. Using his badge, he finally manages to defeat Mr. Pork.

In the meantime, Orihime is confronted by Moe Shishigawara near Sado’s home, who requests that she dies. He attempts to attack her but cannot find the will to do so after looking at her. Moe’s superior Shūkurō Tsukishima eventually arrives and slashes Orihime using his Fullbring, Book of the End. Ichigo and Sado both find Orihime alone and somehow uninjured, and both Tsukishima and Moe have disappeared. An intoxicated Ginjō would later tell Ichigo that Tsukishima is a Fullbringer and the former Xcution leader. Afterwards, he informs Ikumi that he’ll be taking more time off from work and witnesses Isshin and Urahara talking in an alley. He considers following them but decides not to.Ichigo returns to the Xcution hideout for more training and is placed in a fish bowl with Jackie Tristan by Riruka. They prepare to fight.

At home, Orihime talks to Sado through the phone and she explains her encounter with Tsukishima and Moe. She advises Sado to stay cautious of Tsukishima. Sado then returns to the Xcution hideout and asks Ginjō about Tsukishima’s abilities. Ichigo continues to fight Jackie who activates her Fullbring during the battle. They keep on fighting until Ichigo is suddenly enveloped by the black reiatsu emitting from his Substitute Shinigami badge, which causes Jackie to try and stop their training. Ginjō explains Tsukishima’s Fulbring to Sado and they start arguing about the nature of Book of the End. Suddenly, Tsukishima arrives at the hideout looking for Ichigo. He greets his former allies and notes how Jackie and Riruka, who'd left earlier, are both missing. He concludes that they're hiding in Riruka's fish bowl and slices it open despite Ginjō's warnings. The fish bowl opens and a torrent of black reiatsu is released. Ichigo emerges, the black reiatsu cloaking his entire body in the form of a Shinigami's Shihakushō.