ICAC senior principal investigator William Luk delivers a presentation at the PanAsia Convention Against Corruption (PACAC) in W City.

At the contention, his boss Yu Sir introduces him to the legal adviser of the SE Anti-corruption Association, Chief Justice of Asia Emma Pong, who plans to travel to Hong Kong next week to host a forum addressing the issue trafficking sex slaves.

Back in Hong Kong, the ICAC starts investigating the sex trafficking case while Luk's friend and informant, Wong Lam-luk snaps photos of senior customs inspector Kwong Yat-long discussing business with Chumook.

The next day, Luk leads his squad, which includes Kenny Ching, on an operation to spy on Kwong at the Kwai Tsing Container Terminals.

One of the slaves, whose younger sister was killed in the gunfight, reveals to the ICAC that they were from Thailand who were forced to work in clubs in Hong Kong.

Since Pong will arrive in Hong Kong in three days, Yu Hung-sing, the Director of Crime and Security Bureau, sets up an interdepartmental task force with Luk continuing on investigations while Lau is transferred to the G4 department to protect Pong's safety in Hong Kong.

It turns out King works as a mercenary for the mastermind behind the international human trafficking syndicate, Siu Cheuk-ngah.

On the way to the forum, they are ambushed by terrorists on the freeway, leading to a chase and shootout where Pong's assistant, Alice, is wounded.

Fei-hung finally confesses he was paid by Kwong to move the container full of slaves, which he was unaware of the contents, safely to the terminal.

However, a nearby car camera captures the brothers and Luk confronts Ching back in his office.

Pong and Lau's squad arrive at the Hong Kong Cultural Centre where the forum will be taking place.

Luk's subordinate Tammy also discovers through investigation that Pong was involved in money laundering through an offshore company and accepting bribes from Siu, so Luk rushes to the forum to protect Pong, who is the only witness that can pin Siu.

Three months later, Siu manages to scapegoat all his crimes on Chumook, who is sentenced to fifteen years of prison.

Fei-hung is convicted of accepting bribes, but is only sentenced to two years of prison due to cooperation in solving the sex trafficking case.

On 16 December 2019, filming of an explosion scene took place in Tsim Sha Tsui which featured cast members Louis Koo, Julian Cheung, Kevin Cheng, Jessica Hsuan, Bosco Wong and Deno Cheung along with over 100 extra actors.