Gun Metal Grey is a 2010 Hong Kong police procedural television drama produced by Television Broadcasts Limited. It originally aired on Jade from 1 November to 10 December 2010, consisting of 30 episodes. Gun Metal Grey is a dramatisation and fictional telling of Hong Kong's top ten criminal cases, which tells about the complexities of human nature and the strangeness of truth. Gun Metal Grey is written by Lau Choi-wan and Leung Yan-tung, with Terry Tong serving as the executive producer. The drama is one of two grand TVB productions to celebrate the channel's 43rd anniversary, the other being No Regrets, both were the first to be broadcast live in English subtitles. The Chinese title of Gun Metal Grey literally means "criminal police", which can also be used to a describe a cop who commits a crime. During early promotions for the drama, the year "2010" was attached to the Chinese title to prevent confusion with previous dramas of a similar title. The English title is a wordplay on the colour of guns, a representation of criminal justice, and Felix Wong's character Stone Sir, a cop who finds himself trapped in a grey area of morality.

人是否犯法一次，今世就无法翻新呢？十五集剧《命运迷宫》就是环绕这个主题，道尽释囚之苦与悲。豪自小在黑道中打滚，出入牢狱视作等闲，但为人重义气。他为父奔丧而可暂时出狱，但警察标以为他图谋犯事而诸多监视，豪大感精神压力，而热心的社工雯则积极诱导豪重入正途。一次，豪因赶赴为兄弟讲数。导致妻子娟小产，娟见豪劣性不改，伤心失望，与他分手。豪感内疚，雯多加慰解，豪渐受感化而改过。俊被诬陷贪污入狱，出狱后，妻莉携子改嫁陷害他的希，俊痛恨希，后希更害死俊子，令莉神经失常，俊为报仇，不惜加入黑帮走私，泥足深陷。祥是爆窃开锁专家，出狱后打算改过自新，但被处处为难，俊又逼他合谋，祥为筹钱与女友兰结婚，逼于重操故业。俊不择手段向上爬，掀起连翻厮杀，令希入狱，又杀雯母，祥目击，俊要杀祥灭口，豪为义气助祥反击俊……