At Arkham Asylum, Batman clashes with Gorilla Grodd while trying to destroy Grodd's newest invention: the Quake Engine. Amidst the chaos, the engine activates, and the entire asylum suddenly vanishes into thin air—Batman along with it. Once the dust settles, Batman finds himself standing in the middle of an unfamiliar road. He soon realizes that he is no longer in Gotham City—but instead in Feudal Japan!

The amazement quickly fades as samurai descend upon him, seeking to take his life. Later on, Batman's investigation leads him to discover that the one responsible for the kill order is none other than his archnemesis, the Joker. Following an encounter with Catwoman, he learns that the asylum's criminals had teleported there two years earlier—each ruling over a piece of Japan with Joker being the dominant warlord.

In order to return home, Batman must reactivate the Quake Engine, situated in the remnants of the asylum, now known as Arkham Castle. However, there is one problem: aside from his gadget belt, the arsenal that was once at his fingertips is all but gone. Ninja Batman follows the Dark Knight as he traverses a strange new environment, facing off against familiar foes in a bid to return to Gotham in one piece.

[Written by MAL Rewrite]

Within one's Book of Fate is their destiny. Written by the mysterious Story Tellers, these books decide every small detail of one's life. Some Story Tellers, however, choose to interfere with the stories of others rather than write their own. These malevolent beings are known as Chaos Tellers, who seek to ruin stories by overwriting the Books of Fate. Ex, Reina, Tao, and Shane were born with blank books. Ostracized by society due to this abnormality, they abandon their respective stories in search of better lives. In the vast unknown, they encounter famous fairy tale characters such as Cinderella, Momotarou, and Snow White. All the while, they work to subdue the Chaos Tellers and return peace and order to the stories. [Written by MAL Rewrite]

In Shinjuku ward's east side lies Kabukichou, a vibrant city of chaos that glows brilliantly with neon lights but also hides unseen darkness. Employed at a university hospital on the west side, John H. Watson is looking for someone who can assist him with an odd case. His search leads him to the Pipe Cat, an underground bar that serves as a meetup venue and job board for some of the best detectives in Shinjuku, the most prominent among them being Sherlock Holmes. Upon finding the bar and meeting the peculiar investigators, John learns that they are pursuing a case involving Jack the Ripper, an infamous serial killer. Due to subsequent events, John ends up driving Sherlock to the crime scene of a murder supposedly carried out by Jack the Ripper. Even though John is only there to enlist Sherlock's help with his case, he witnesses Sherlock brilliantly uncover the truth behind the crime scene. However, he begins to realize that Sherlock is not only a genius detective but also an eccentric character. As John continues to request Sherlock to assist him with his case, he finds himself spiraling into the detective lifestyle of solving cases beyond the minds of ordinary civilians. Through this work, John begins to see the true colors of the chaotic city that is Kabukichou and starts to unravel the unsettling mystery behind his own case.

Two OVAs released with the 8th and 10th volumes of the original novel. They fall chronologically between the first and second seasons.