Sam is an organised crime boss and he has a plan. Inspector Wong is the police officer in charge of beating organised crime, and thus Sam, and he has a plan too. They both want to win and they both know what the other is up to, and that is infiltrating their organisations with moles, so for an hour and a half you're wondering who's going to get found out and if they are actually a good or bad guy. This tension carries right up to the end and indeed beyond it (hurray for films that don't provide ultimate finality). While there's very little actual action in this film, the suspense, script and acting will keep you engrossed to the end and maybe into the pre&sequels :-)