Line Walker is a 2016 action thriller film adapted from the 2014 TVB series of the same name. Directed by Jazz Boon and starring Nick Cheung, Louis Koo, Francis Ng; Charmaine Sheh, Benz Hui and Au Siu-wai reprised their roles from the original drama. It was released in Hong Kong and Mainland China on 11 August 2016.

Plot

Inspector Q (Francis Ng) and agent Ding Siu-ka (Charmaine Sheh) are top members of CIB Department, they are after a drug racket that is taking over the city. Unexpectedly, they receive a mystery message from a missing undercover agent "Blackjack". CIB tries to locate and process Blackjack before it's too late. The paranoid drug mafia leader Tung Pak-ho (Li Guangjie) plays his own troop on each other's throats, suspecting a mole. Meanwhile, boss Blue (Nick Cheung) and his right-hand man Shiu Chi-long (Louis Koo) participate in an internal struggle to become the top dogs irrespective of their strong friendship.