As cadets, Lau and Chan both show promise as police officers. However, Chan is removed from the training and send to be a long-term undercover in Sam's gang. However, unbeknownst to the police, Lau is also a long-term mole who is feeding information back to Sam. When Sam and police chief SP Wong both have their operations scuppered, each realises the other has a mole and sets out to uncover each. With each other's lives at risk, Lau and Chan must be the first to uncover the other.
I decided to see this after hearing good things about it but I was conscious that often foreign films can be given more leniency than Western films doing the same thing. After a slightly confusing opening few moments as characters settle down (not helped by using completely different actors for characters at late teens and late 20's - do people change that much?) the film immediately becomes gripping. The plot may well have the occasional hole and have unnecessary personal details (Lau's girlfriend and Chan's ex weren't really needed) but the central story is well written and told with such urgency that it is hard not to be totally engaged.
The film doesn't have many massive shoot outs or action scenes but it has a pretty consistent sense of tension that is enjoyable right up to a typical but impacting ending. The direction is stylish and only occasionally overuses the slow-mo jump cuts. It may owe more to American cinema than that of the Orient but it is still a very good film and I hope the inevitable remake will be as good.
The cast don't need to do that much apart from look intense and portray the tension of the story in a realistic fashion - something that they do well. At times the lead two actors are pushed out of this by the personal asides but they happily keep things on track. Both Lau and Leung play it very well - it never came down to good guy/bad guy and the audience was pretty well split. Wong is a solid officer while Tsang is good as Sam. Chen and Cheng may not have a great deal to do apart from slowing the film but they both look good doing it.
Overall this is a solidly enjoyable cop thriller, regardless of what country it comes from. It will eventually be remade I imagine and when it is I hope that it manages to retain it's consistent sense of tension, double-edged characters and a real tight hold on it's audience just as this did here.
