There are some very good reviews already posted about "Infernal Affairs", although they got some minor facts wrong (such as which actor played which role). This review will look at differences between this film and "The Departed"--for Scorsese fans who enjoyed his version and now wonder if they should see the original.
Yes, they should see the original.
Scorsese did a remake which followed the original storyline closely. Scorsese's style, as always, is marvelous. His work is more controlled than usual--no digressions into extended violent scenes (as in Casino, although "The Departed" film is much more violent than "Infernal Affairs"), no plot diversions into draft riots during the Civil War...etc.
However, the Scorsese film--which I enjoyed and was his best film in years--left me unsatisfied, while "Infernal Affairs" was extremely satisfying. Both films are tragedies, but the drama is far more deeply felt (for me) in "Infernal Affairs" than in "The Departed".
The answer lies in the difference in approach between the film making cultures of Hong Kong and Hollywood. Between what each culture feels the audience wants. Between the pressures of a higher budget and bigger stars. Scorsese, whether the actors asked for it or not, clearly felt a need to give the principal actors meatier roles. The film brothers who made the Hong Kong original only wanted to get the job done--a crisp story that did what it needed to, and then got out.
The Hollywood version takes a lot of time to provide additional detail to the story to flesh out the characters and give them showy scenes. "The Departed" runs about forty minutes longer than "Infernal Affairs". It adds a love interest (which really goes nowhere) and a lot of character details. Probably worse...
SPOILER ALERT SPOILER ALERT
...the Scorsese film attempts "justice" at the end. It is perhaps an American need to tie up loose ends, to make things right. Maybe it is the pressure stemming from a bigger budget, and needing to satisfy a larger audience. But dramatically, the Hong Kong version had it much better.
REALLY SPOILERS, REALLY! DON'T READ IF YOU HAVEN'T SEEN THE DEPARTED!!!! STOP!!! WHAT'S WRONG WITH YOU???
In the Scorsese version, an additional character, played by Mark Whalberg, is added to create justice--someone, in the end, to bump off the Matt Damon character. The problem with this is dual. First, it creates a huge plot hole--if Whalberg is around, then there is someone to prove that the DiCaprio character is really a cop, so much of how the film ends simply makes no sense at all. DiCaprio does not need to get Damon to prove he is an undercover cop if Whalberg is around. And, why does Whalberg remain in the background instead of going directly to his superiors? Why does DiCaprio not seek out Whalberg?
No, sorry Marty. None of it really works. Whalberg is only there to kill Damon in the end.
But this is very misguided. I personally felt a lot of involvement with the DiCaprio character. When the bad stuff happened to him, I felt the tragedy, but when Whalberg bumps off Damon, I felt cheated.
If the movie was going after justice, why not just have an ending with DiCaprio living? But this is the big budget American idea of entertainment, I guess--a more or less happy ending, even if it completely screws up the story.
So while I enjoyed the film, I walked out unsatisfied.
Then I watched, a few days ago, the Chinese original. The ending is far more cynical, and as a result works a lot better. There is no Whalberg character, no big plot hole. In addition, the film was faster and cleaner, much less showy. No bigger role for Nicholson to strut his stuff. No extraneous love interest. Not as much explicit violence to give the audience a cheap thrill.
Less Hollywood over the top and pandering to the audience was what makes "Infernal Affairs" the superior film--and one worth buying, as you'll never see it on tv.
Oh well, guess this means Scorsese will send Joe Pesci after me!