Across four seasons and one feature film, Bungo Stray Dogs has crafted a rich narrative that adapts not only the original manga but several of the novels. Of the ten published, eight have been written by series author Kafka Asagiri, and while some have already been adapted, there are others that have not yet, begging to question which will come next.
These novels, far from supplementary content, expand on the world of Bungo, as well as reveal insights into characters’ pasts and the events that have shaped the story fundamentally. Most anime fans familiar with the existence of these novels might think that the anime only started adapting them at the start of Season 2, but in fact, the anime has been implementing them from the beginning. For the sake of this article, this will only be a discussion of the novels written by Asagiri. Of the remaining two, one is a novelization of the movie Dead Apple by Hiro Iwahata, and the other is a novelization of the early episodes of the anime by Mari Kosaka, intended as a children’s book, funnily enough.
Osamu Dazai’s Entrance Exam
The first novel is a very peculiar case, because, through the anime, the context of the story was altered considerably. Anime watchers will recall Episodes 6 and 7 of Season 1, which involved an investigation of the Azure Messenger and its ties to an old investigation. In the novel, these events happened before the events of the anime, before Atsushi was brought into the Agency.
As the title suggests, this case was Dazai’s entrance exam to the Armed Detective Agency, but in the anime, it's just another investigation set after Dazai becomes a full-fledged member. It’s unclear why exactly this was changed, but it might have been to give Kunikida more of an arc within Season 1. The conclusion affects him and informs how he acts later when he discourages Atsushi from saving Kyouka before he's proved wrong by Atsushi's bravery.
By the end, it’s a clever adaptive choice that is often forgotten either because fans are unaware of its origin as a novel or because every other novel adaptation is more clearly labeled. From the very start of Season 2 onward, each season would begin with a novel adaptation, typically set years prior to the start of the anime.
The Prologue Arcs
The second novel, Osamu Dazai and the Dark Era, is the story that changed everything. Although Dazai is the titular character, it’s just as much about Oda Sakunosuke, the pyrrhic figure at the heart of Bungo’s story. When their mutual friend, Ango Sakaguchi, is kidnapped, Oda investigates only to stumble upon a conspiracy that puts him in the sights of a powerful foe. It is the story of friendship lost and how Dazai left the Port Mafia.
When this story was adapted into the anime, it initially threw some fans off simply for how different it was. For those that stuck with it, it remains one of the most memorable and defining stories in the series, and one that feels especially steeped in neo-noir and gangster film influence. Altogether, a classic.
Season 3's prologue adapted Asagiri's seventh novel, Dazai, Chuuya, Age Fifteen, which chronicles Dazai’s budding partnership with Chuuya, who is initially quite antagonistic toward the Port Mafia. It follows the two of them solving a mystery that ends up revealing the origin of Chuuya’s incredible powers, culminating in his joining the mafia.
The third novel, The Untold Origins of the Detective Agency, wouldn’t be adapted until this year’s Season 4, coinciding with Ranpo’s much bigger role. It tells of Fukuzawa’s first meeting with Ranpo, the mystery they solved together, and how they grew close, leading to them building the Agency around Ranpo’s talents as a detective. However, the novel actually goes a bit farther.
The first part of the novel, which is omitted in the anime, sees the characters pondering the origins of the Agency, all while trying to figure out what Atsushi’s entrance exam should be. Altogether, not an essential detail to include when the audience already knows what happened, which is a recurring theme in the omitted details from some of these adaptations.
The Un-Animated Novels
It is here that we get to novels that have not been animated, starting with Gaiden: Ayatsuji Yukito VS. Kyogoku Natsuhiko. It's the only novel by Asagiri that has not been translated into English. It did, however, receive a radio drama and a manga adaptation. It follows homicide detective Yukito Ayatsuji and agent Mizuki Tsujimura solving a murder case. This is by far the most separate story from the main happenings of the series.
Fans of the film Dead Apple might recognize Mizuki from her cameo appearance. Although, anime-only fans likely were scratching their heads, wondering if they were supposed to know who she was. Otherwise, the characters from this story have not appeared yet, but the story sounds interesting, so hopefully, it will get an adaptation.
Next up is 55 Minutes, the plot of which has to be one of the most exciting yet and the one most perfect for a feature film if Bones ever decides to follow up Dead Apple. It begins with Yokohama being completely obliterated, only to go back 55 minutes prior to the beginning of the story, with the Agency on a special assignment. It also introduces characters such as Jules Vern and H.G. Welles.
Bungo Stray Dogs: Beast is an alternate universe story, imagining what would have happened if Dazai recruited Atsushi into the Port Mafia instead of Akutagawa. It is a seemingly disconnected “what if?” story that reveals itself to be far more connected than initially thought. It was adapted into a live-action film and has received a manga adaptation with art by Shiwasu Hoshikawa
Finally, Storm Bringer follows Chuuya as he settles into his life in the Port Mafia when a man named Paul Verlaine appears. Verlaine promises to kill everyone Chuuya cares about, prompting him to team up with a European investigator named Adam to stop them. It was adapted into a stage play in 2022 and explores more of Chuuya’s origins.
What Will Get Adapted Next?
Of the eight novels that Asagiri has written, four of them have already been adapted into animation, and all the others besides 55 Minutes have received other forms of adaptation. Beast got a manga and a live-action film, Gaiden was a radio play, and Storm Bringer was a stage play. Whether any of those get told in the anime or not depends on if the production committee feels it’s warranted.
With Bungo Stray Dogs Season 4 at its end, fans will likely be left on a cliffhanger. Thankfully, the next season is coming sometime in July 2023, but the current arc isn't finished in the manga, so there's plenty of time to kill with a new book adaptation. The most logical choice would be 55 Minutes, which sounds perfect for a big feature film, but any of these novels would make for a great addition to the anime.