Untold Origins Arc

The Untold Origins Arc (設立秘話編,) is the first background arc of the Bungo Stray Dogs series. It tells the story of the first encounter of Yukichi Fukuzawa and Ranpo Edogawa which led to the founding of the Armed Detective Agency.

Synopsis
A chance encounter leads professional bodyguard Yukichi Fukuzawa to begrudgingly take an arrogant boy genius named Ranpo Edogawa under his wing. Their first job brings them to a local theater on high alert after receiving a bizarre death threat — a challenge that will require both Ranpo's brains and Fukuzawa's experience. The aftermath spurs Fukuzawa to establish the Armed Detective Agency.

Chapters

 * From the The Untold Origins of the Detective Agency novel


 * A Day at the Detective Agency
 * The Untold Origins of the Detective Agency

Impact

 * Fukuzawa quits his job as a professional bodyguard but gets hired regularly as Ranpo's subordinate in his detective cases.
 * With Natsume's backing in acquiring a Skilled Business Permit, Fukuzawa founds the Armed Detective Agency, with Ranpo as its first member.

Light Novel–Anime Differences

 * The anime includes Ōchi Fukuchi specifically inviting Fukuzawa to join the military police and helping Fukuzawa later on to visit Oda in his cell.
 * In the anime, Oda is not with a sack while restrained and while skirmishing with Fukuzawa. He is also not shown being incapacitated by Fukuzawa after shooting the S&K Corporation secretary.
 * Ranpo's parents are only briefly mentioned in the anime, unlike in the light novel where Ranpo expounds on his father's and mother's profession and qualities.
 * Ranpo's expression of his inner feelings during the theater play is much more subdued in the anime, unlike in the light novel where he is depicted to be screaming in anguish among the audience.
 * The events surrounding Murakami's faked death and ultimately being exposed by Ranpo are relatively quicker in the anime. For example, the anime omits the details that Murakami has died en route to the hospital after his onstage death, only to be revealed later to be bogus.
 * Unlike in the light novel, Oda's incarceration in the anime does not show him chained and restrained in a straitjacket; he instead retains his typical clothes. He also has been given and reads the Bible in his cell.
 * The anime shows Oda eating curry from Freedom Restaurant as promised by Fukuzawa. This is not shown in the novel.
 * In the anime, Fyodor Dostoevsky briefly surfaces after the V incident, muttering that the name "V" is read as "five". This is not shown in the novel.