Asia's safest city is about to be tested.

Five police officers in Hong Kong are kidnapped. The police commissioner is on a business trip overseas. Two vice commissioners, Sean Rau and M.B. Lee, then take over the case. The two vice commissioners are rivals who both vie for the police commissioner seat. At first, M.B. Lee takes the lead in the case, but comes to a dead end. Sean Lau then takes the lead, but he falls into a trap. Both men are then investigated by the ICAC (Independent Commission Against Corruption).