The Apothecary Diaries Film Casts Miyuki Sawashiro and Ai Mikami in New Trailer

The Apothecary Diaries: The Late Lady's Treasure revealed Miyuki Sawashiro as Ruochin and Ai Mikami as Inshan in a character trailer released on October 14. The film opens in Japan on December 11, and the footage connects both original characters to the mystery awaiting Maomao and Jinshi on the big screen.

Ruochin and Inshan enter the film's central mystery

Ruochin is introduced as a middle-ranking consort who died in the rear palace five years before the film's events. Her final wish was for her remains to be returned to her homeland after five years, making her the deceased woman at the center of Jinshi's new assignment. Sawashiro provides her voice.

The official story setup says Jinshi examines Ruochin's remains before the journey and discovers that her body is still in pristine condition. He then brings Maomao to Binan-shu, a southern province ruled by the Bi clan, as they investigate the unexplained preservation and carry out the return of the consort's body.

Inshan, voiced by Mikami, previously served as Ruochin's head lady-in-waiting. The character material also places her in service to Mu Qing in the present, linking her past duties to another part of the film's cast. The trailer presents Ruochin and Inshan together, establishing their relationship without disclosing how much Inshan knows about the mystery.

Their introduction adds a personal connection to the film's larger treasure plot. Maomao and Jinshi arrive in a city on the water while pirates search for treasure left by their former leader, and a major incident occurs on the day scheduled for Ruochin's funeral.

The new cast joins an original theatrical story

Sawashiro said the role allowed different interpretations to emerge while she studied the script and recorded in the studio. Her comment leaves Ruochin's true nature unresolved, matching the questions raised by the unusual condition of the character's remains.

Mikami said she was already a fan of the television anime when she received the role. She described the film as a large-scale puzzle mystery intended for both existing fans and newcomers. Inshan marks her second anime film performance after voicing Rita in All You Need Is Kill.

The Late Lady's Treasure is the first anime film in The Apothecary Diaries franchise. It uses a new story concept from original light novel author Natsu Hyuuga instead of adapting a previously published arc. Norihiro Naganuma directs the feature, while TOHO Animation STUDIO handles the animation production.

The latest trailer follows earlier character reveals for Maomao, Jinshi, the Bi clan, and the Kajadan pirates. Together, those groups frame the film around three connected elements: Ruochin's preserved body, the political territory Maomao and Jinshi must enter, and the treasure sought by the pirates.

The next confirmed milestone is the film's theatrical opening in Japan on December 11, 2026.