Ten years ago, Darker orchestrated a mysterious explosion of Mang Wan, the girlfriend of police inspector Law Fei, with the only survivor and witness being Wong Siu-ping, a homeless man who was disabled and his face severely burnt and disfigured as a result.

Darker reappears again in the present sending out death notices and executing violent and brutal punishments, challenging the police to a face off with an unimaginable conspiracy behind.

[3] News for the project did not surface until Zhao Haohui posted on his Sina Weibo in February 2018 stating a film adaptation of his novel will begin shooting in July of the same year with Koo, Cheung and Francis Ng confirmed to star.

On 16 April at 6:00 AM, filming of a firearm shootout scene took place in an apartment building in Sham Shui Po with cast members Ng, Cheung, Wu and Babyjohn Choi.

[8][9][10] On 2 May 2018, filming took place at the Lei Yue Mun Park and Holiday Village, where the film's production start ceremony was also held with director Yau and cast members Koo, Ng, Cheung, Wu, Chrissie Chau, Timmy Hung, 6-Wing, Justin Cheung, Babyjohn Choi and Tony Hung present.

[11][12] Death Notice was originally set to be theatrically released in Hong Kong on 9 December 2021,[13] but it was later pushed back to 31 March 2022, with "marketing correction" being cited for the reason.