Such a great movie that's unheard of, the script is so well written and original, with great suspense and thrill, acting is very well performed and setup is convincing, which makes this certainly one of the best crime thrillers. Unlike most of the overrated boring movies bloated with fake reviews this is a solid movie that's a bit underrated, highly recommended.

A cop Kim Seong-yeol (Cha Seung-won) is a wrecked: He has been unfaithful to his wife years ago and thus indirectly inflicted the death of his young daughter! His wife, Ji-yeon (Song Yun-ah) lives since then like a recluse and Seong-yeol is plagued by guilt. He and his hated colleague Choi (Park Won-sang),take over a murder case. The victim is the brother of gangster Jae-kal (Ryoo Seung-yong) - and Seong-yeol finds evidence at the scene, indicating that his wife was present there. Seong-yeol obliterates all traces, but soon has a blackmailer on the neck, which is in the possession of some surveillance videos!

Yoon Jae-gu established himself in the Korean Cinema with his debut script: the captivating thriller Seven Days. Now he already puts his directorial debut - not surprisingly, this is also a thriller. But "Secret" has at least many elements of a drama, and finally you will end up watching a tension and emotionally driven plot with two protagonists. You will never find out that the guy behind the camera is a debutant, one would think "Secret" is the work of an experienced director.

This statement holds both praise and criticism: Praise to the effect that it is technically excellent. The imagery is full of noble compositions and neat look. The actors perform excellent, the soundtrack creates mood, the drama slowly pulls on the tension screw. All elements are absolutely exemplary.

But that is nagging at high levels: Primary you can cheer at "Secret". The gigantic Cha Seung-won (Eye for an Eye) carries the film as a cop sovereignly on his shoulders; his figure is drawn diversely and excitingly. One has to pity the man entirely, even if never is in doubt that he has a bad character. The death of his own daughter is more than enough punishment and that he is now once again dragged into a vortex of tragic events, makes room for quite sympathy.

Song Yun-ah (Arang) on the other hand is had almost too much sacrifice. Her chalk white face resembles of a corpse, and sometimes it is difficult to fully empathize with her. She gives a solid performance. But the biggest joker should be Ryoo Seung-yong (Possessed),who is close to the limit for charging the gangster with gusto. Because even convince the supporting cast, it's no secret: The cast gets a thumbs-up. Also, special mention, the whole technical team is fantastic.

Though "Secret" comes to its excessive length and sagging, has yet provided enough voltage for questions - who is the unknown blackmailer? How deep wife Ji-yeon is involved in the matter? Why did she flip the gangster's brother? Has it ever? Or there is a surprise at the end, which again puts everything previously narrated on the head? Once again Koreans deliver a mainstream thriller entertainment on an international scale. This really is not too bad.

Unlike the first reviewer of this movie here on IMDb, I found Secret/Sikeurit (a 2009 Korean movie) to be quite entertaining, and solid enough to recommend it as a worthwhile watch.

SPOILERS AHEAD!

This movie is categorized as a thriller; a genre that often encompasses a very broad range of films. More specifically, "Secret" falls into the sub category of being a Suspense/Mystery/Crime/Drama film. There's little to no action involved here save for the penultimate climatic scene, and that scene is the by far the worst part of the movie in my opinion. It's the 'before and after' the climax where this movie clicks, and often clicks quite well.

What we basically have here story wise is as follows: A detective is investigating a murder in which clues to the case continually lead to his semi-estranged wife. It's a fairly formulaic and straight forward premise at its core: Is wife guilty?...Should detective protect wife if so?...Will the outcome result in wife and hubby reconciling?...Is there something else going on that isn't quite apparent?...etc...

I thought the story, script, and plot of this movie were all relatively strong overall. The film did keep me watching, and I was interested enough in the mystery and eventual outcome throughout. It was fairly well paced as well, and was accorded solid performances by the leads throughout.

Overall, I very much enjoyed this movie. My primary issue with it is the climactic action scene that seemed to be completely out of tone with the rest of the film. This scene really should not have been included in the film at all, or, it should have at least been more restrained in order to result in a more convincing outcome. However, I'm fairly confident the director's intent for including this scene was to actually provide the viewer a "red herring" of sorts, and it was certainly effective in accomplishing that. Red herring or not, this scene definitely could have been tamed down quite a bit, or reworked in another equally effective fashion to better accompany the film as a whole. I feel this is a movie that would have been much better served by having no action scenes in it whatsoever.

Bottom line: I'm giving this film a 7 for the rating that will accompany this review.

P.S. FYI; As is becoming more prevalent these days in cinema from across the globe; it's VERY important to NOT stop watching this movie until the end, AND, until after the credits have rolled!