Detective Dee and the Mystery of the Phantom Flame

Detective Dee and the Mystery of the Phantom Flame is a 2010 ChineseHong Kong action mystery film directed and produced by Tsui Hark, and features art direction and fight choreography by Sammo Hung, and stars Andy Lau as the titular protagonist. The supporting cast includes Carina Lau, Li Bingbing, Deng Chao and Tony Leung Kafai.

In year 689 of the Tang Dynasty, Wu Zetian is about to be crowned the first Empress in China despite opposition from Tang officials. To mark this occasion, she has a colossal Buddha figure built overlooking her palace. However, an official inspecting the Buddhas progress mysteriously erupts into flames. Penal officer Pei Donglai and his superior investigate and interrogates the supervising builder, a man named Shatuo, who was formerly imprisoned after he took part in a rebellion eight years ago. They find nothing, however, and Peis superior dies soon after in the same manner as the official.The Empress orders former detective and rebel Di Renjie be released from prison after the Imperial Abbot state preceptor states that he must solve the mystery of the fire. She sends her attendant Shangguan Jinger to fetch Di from prison, where they are attacked by assassins. Wu reinstates Di as the royal detective and assigns Jinger to be both an assistant and spy. On Wus orders, Jinger attempts to seduce Di, but they are interrupted by assassins. Di meets Prince Li, who fails to recruit him into leading a rebel army. When Pei takes Di and Jinger to inspect the charred corpses, Di deduces the assassins use a poison that ignites upon contact with sunlight. ........

Source: Wikipedia