When Inspector Chan (Eric Tsang) -- a cop on the edge -- is put in charge of recruiting a new elite police squad, he picks loose-cannon academy rejects Jack (Nicholas Tse), Match (Stephen Fung) and Alien (Sam Lee), along with the tough and beautiful Y2K (Grace Yip). Tasked with bringing down an ultraviolent crime kingpin (Tôru Nakamura), the superhip mod squad must go undercover to get the goods on the gangster in this explosive action thriller.