Tony Leung Chiu-Wai did not receive an Oscar nomination for portraying Chan Wing-yan in Infernal Affairs.
Tony Leung does not play the corrupt cop though and is instead the honest cop who pretends to be a gangster to infiltrate the mob/Triad boss. This part was played by Leonardo DiCaprio in The Departed, but the character is a bit different from the one in the remake. Where The Departed depicts DiCaprio's character freshly into the undercover game Chan Wing-yan has been in the life for ten years when we first meet up with him so Leung's performance is in turn rather different in approach. Leung himself is no stranger to playing undercover cops having played one in Hard Boiled, although Chan Wing-yan is a very different undercover cop than the one he played in that earlier film.
The underlying factor to much of his performance is expressing the exasperation in his character who has been undercover for far too long. Leung is extremely effective in bringing this out in his cahracter that suggests the experience of his character. Leung's doesn't portray the cop as ready to jump to every task and really make himself deep into the good graces of the crime boss, instead interestingly Leung plays him as a man who to some degree is rather bored with his job. This is of course a rather difficult approach to take as the character could seem boring himself, but Leung gives the right complexity to these feelings to allow us insight into a cop who has been pretending to be a criminal for his whole career.
Leung is very affecting in his role in that he shows that Chan isn't tired of the job in that it is not interesting or anything like that but rather tired of playing the bad guy all the time when he is in fact the good guy. Leung is careful in his portrayal in he is able to be the man fed up with being the bad guy well properly playing the part of the bad guy at the same time. Leung is quite excellent because he has a little bit of fun in his performance in giving off the vibe of the punk who is living loose and just is up for the next deal, but within this he is able to express his problems within this very same thing through a distinct lack of satisfaction during any point he is taking part in the crime boss's plan.
This being a performance by Tony Leung there is a great deal of charm in his performance. Leung measures it perfectly though never overplaying his hand yet still bringing in just the right amount to make it very easily to like Chan as well as really feel for his plight throughout the film. He has some very nice moments that lets us see Chan as more of a man than just in his current situation, and we see some of the ways he tries to alleviate his feelings. Leung is always great in these fairly simplistic moments like his romance of sorts with his therapist because he just brings these moments of just the slightest of joys in his often downbeat man in such a genuine fashion.
Something rather interesting about Leung's performance is he doesn't play it in a very heavy fashion, yet he never once feels even slightly inadequate in any scene. He is able to bring the anguish and the pain that he feels but he very much pulls this into his performance as Chan who really can't show that and has to keep up the facade of aloofness most of the time. Leung absolutely makes this work in a fashion that establishes always the way that Chan is playing a part the part of a man who really does not care about much of anything, but even behind the part that he is playing there is an emotional man who is coming very close to being fed up with his false life of crime he must continue to live.
Leung approach pays off extremely well for any scene where Chan is either allowed or forced to express his own feelings without any screen put above it. Each of these moments Leung makes a tremendous impact with and they have a great power especially due to the reluctance he shows otherwise. One of the most moving scenes in the film is Leung's heartbreaking reaction when one of Chan's few actual friends is killed. It is a very poignant scene, and a challenge as their scenes have been somewhat limited beforehand yet Leung absolutely brings the heart the scene needs. In his silent emotional response Leung expresses how the death devastates Chan not only because his only official connection dies, but also really his only friend.
Leung is brilliant as such a unique hero who must play the morally bankrupt yet is the most moral man in the entire proceedings. His performance works in so many ways. He also works as the man of two sides always trying to do one thing well doing the other in tandem. He also acts as the more traditional hero who we become invested in as he tries to do good. He makes the longing to do the right thing so very real and the moment where it appears he has won is especially satisfying with Leung portraying Chan finally getting to show his true colors. Leung's quiet dignified portrayal of this most moral man I found grew on me substantially throughout. He made it so the final moments of this film, where he is barely on screen, were even more moving than I expected them to be, and made it so the ending (which I thought might be unsatisfying in some way) to be truly profound.