[2] The film was narrated from the point of view of the protagonist, Fang Hongye, on a series of murders at the Shen's Family Fort.

Shen Qing's wife, however, insists on waiting for the arrival of three brothers, known as the 'Four Phases of Heavenly Thunder,' before taking any action.

A mute servant girl Ah-Zhi leads Hongye to a secret gunpowder storage room, raising suspicions.

It was revealed that six years earlier, Yu Zhen established the Shen's Family Fort to secretly develop an alloy for gun barrels of powerful weapons.

After completing the weapon, Yu Zhen orchestrated the butterfly murders (and forged the eight pages of "Hongye's Notebook" mentioned in the beginning of the story) to eliminate rivals and claim dominance in the martial arts world, manipulating Tian Feng to assist him unwittingly.