鬼才・西尾維新が12ヶ月連続刊行して話題となった、同名の大河小説のテレビアニメーション版。「刀を使わない剣士」という特異な設定の主人公と、１つの能力に特化した「変体刀」と呼ばれる、12本の刀を持った者たちとの戦いを描いている。刀を使わない剣術「虚刀流」の七代目当主の青年・鑢七花は、姉の七実とともに不承島でひっそりと暮らしていた。しかし、島を訪れた奇策士・とがめの言葉により、伝説の刀鍛冶「四季崎記紀」の作った刀、完成形変体刀十二本を集めるため旅に出る……。監督は元永慶太郎、シリーズ構成は上江洲誠、アニメーション制作はWHITE FOXが担当している。
In an Edo-era Japan lush with a variety of sword-fighting styles, Shichika Yasuri practices the most unique one: Kyotouryuu, a technique in which the user's own body is wielded as a blade. The enigmatic seventh head of the Kyotouryuu school, Shichika lives quietly in exile with his sister Nanami until one day—the wildly ambitious strategist Togame barges into their lives.
Togame brazenly requests that Shichika help in her mission to collect twelve unique swords, known as the "Deviant Blades," for the shogunate. Shichika accepts, interested in the girl herself rather than petty politics, and thus sets out on a journey. Standing in their way are the fierce wielders of these legendary weapons as well as other power-hungry entities who seek to thwart Togame's objective. In order to prevail against their enemies, the duo must become an unbreakable team as they forge ahead on a path of uncertainty and peril.
