The eighth informant is the fake old Zuo: Gu Sanxing, who lives with the fake pigeon Li Man under the careful planning of Du Shengkui. However, the net law is slow and elegant, and his real identity is an omnipotent latent spy, that is, the man who died but didn't die. In the end, his confession made the arrogant Du Shengkui nervous breakdown.

Reporter Li Man: She was put in a pre-arranged prison, released with pigeons, killed pigeons at home, and lived with Lao Zuo as an impostor for many years.

Whistleblower Wu Chuishui: Wu Chuishui is a vulgar writer, claiming to be a lover, deceiving many girls' feelings, leading a lazy life and actually being a liar.

Informant Yu Yueshan: Yu Yueshan is Du Shengkui's pawn and deserves to die. Although I got six points, it didn't help much.

Gao, informer: Gao is the owner of a tailor's shop. She used the opportunity of making clothes for her ex-wife who was an official to sell black market jewelry and opium. Although I got six points, it didn't help much.

The Informant changed the scene of trembling and bullets in the spy war drama, but continued the mysterious and rigorous thinking in Liu Yunlong's works and told a strange and gloomy suspense story. The dragonfly played by Liu Yunlong is a public security officer who is loyal to his career and love. From the discovery of headless bodies in wailing wall to the examination of boiled bones, dragonflies remain calm and rational even when beloved pigeons become the focus of all contradictions. Liu Yunlong's restrained and steady performance style brings this role into full play.

The story took place in the 1950s. Longfei, a policeman from Beijing Public Security Bureau, and his colleague Ying Hongshan were ordered to start a new job in Jiangnan. Many years ago, Long Fei, who was still an underground worker, and his former lover pigeon worked and lived here. Later, due to work arrangements, the two separated, and the whereabouts of the pigeon are still unknown. Later, in the course of work, Longfei found that the arrest of martyr Jiang Ren was inextricably linked with pigeons. With the cooperation of Hongshan, Longfei found witnesses Du Shengkui, Peacock and Falcon, and obtained important evidence from them. However, the working process of dragonflies is sometimes clear and sometimes confusing. Who betrayed his comrades who worked underground in those days? What does the former lover pigeon have to do with this? Dragonfly finally dispelled the heavy fog, the suspense was uncovered, and the truth was revealed.