China's first animated detective film 'Mystery of Chang'an' marvels audiences

"Mystery of Chang'an," China's first animated detective comedy, premiered in Beijing on Thursday, bringing some of the most innovative and memorable scenes in the country's animation history to the big screen.

Creators of "Mystery of Chang'an" pose for a photo at the film's premiere in Beijing, Aug. 6, 2026. [Photo courtesy of 10M House Animation]

Directed by Cheng Teng and Benjamin Huang, the film, also known as "Demon Agent," follows a sharp-tongued young detective and a pure-hearted wolf demon constable who are forced to team up on a murder case. The film is set in Chang'an, the capital during the Tang dynasty (618-907). The city has been reinvented as a fantastical metropolis where humans and demons live together in peace. As clues point toward the heart of the city, the unlikely duo embarks on an adventure to protect the metropolis while uncovering the secrets that lie beneath its bustling surface.

Cheng, director of the 2020 animated blockbuster "Legend of Deification" and a fan of mystery and puzzle-solving stories, said at the premiere that this was a great opportunity to explore animation as a medium for such narratives in a more imaginative and entertaining way. "Animated films are an art form of imagination and visual impact — that is precisely where the strength of animation lies," he said, adding that the film was a huge undertaking that took six years to make.

Producer Cao Zijian stressed that just as live-action movies span many genres, he also wanted to bring more diversity to animation when approaching this film. "I hope that in the future, Chinese animation can embrace a wider variety of genres, so that audiences can find their own favorite animated styles. With this film, we are taking at least a small step forward — even if it's just half a step. We don't want the word 'animation' to define or limit what animation can be," he added.

The highlight of the film is the city of Chang'an, a marvel of a "clockpunk" world incorporating a local aesthetic never seen before in Chinese animation.

"We built a fantastical world rooted in Eastern imagination, blending the Tang dynasty capital with intricate mechanical structures," director Huang said. "In this city, everything runs on gears and mechanisms — flip signs, aerial tracks, mechanical restaurants. We wanted audiences to feel both a sense of familiarity and wonder," he explained.

He also revealed that when deciding how to create the visuals for the perpetual motion machine called the "Heart of Chang'an" at the city's core, the animators wanted to depict a balanced, eternal movement, but also needed a strong emotional core to drive it. "In the end, our visuals achieved that effect — it's stunning. We hope the audience can feel that too," he said.

The film received rave reviews from both adults and children at the premiere, and is set for release on Aug. 22.