This is the best of the three Vengeance films in my view.

Rating: 10/10 (14 September 2013)

The film opens with Oh holding a business man by his necktie to keep him from dropping off a building.
Flashback to Oh in a police precinct for extreme public drunkenness. A friend comes to pick him up. While the friend talks to his wife, Oh walks off. Years pass while he is imprisoned.
He gets to watch a newscast that claims he killed his wife. He has a bit of a breakdown at that point, seeing ants coming out of his flesh and the like.
He writes lists of all his wrongdoings and the people he has offended. It's more than half a dozen notebooks.
Early on, he tries to kill himself, several times. He gets over this, and starts to keep track of time and to tone his muscles.
After 15 years, he is dumped in a suitcase on the top of the building he was held in. The man in the first scene was a suicide. Oh tells the suicide his story, then does not listen to the other man's story. Nice. 'Laugh, and the world laughs with you. Cry, and you cry alone.' This was on the wall in his cell; he repeats it, laughing, after the suicide kills himself.
Oh's house is gone, demolished and replaced. His relatives and friends think he killed his wife, so he cannot contact them.
An encounter with street thugs shows his training paid off. Some stranger gives him a mobile phone and a wallet with money. A 'scholar of Oh Dae-su' calls him, and they have an oblique talk.
He and a chef at the first restaurant he visits strike it off quickly. She helps him find what he is looking for.
He finds the prison from the taste of fried dumplings. He finds an audio tape of the person who commissioned his imprisonment. The prison had a lot of guards, and he did a lot of fighting to get free of them.
'Revenge or the truth? That's a problem for you.' Great line. In this case, truth was the ultimate revenge.
The mystery is quite intricate, and the protagonist needs much help to resolve it. One needs a strong stomach to finish the material, but the film is well worth finishing.
Cinematography: 9/10
Sound: 8/10 Music was a bit much for a few minutes of the film.
Acting: 10/10 The adversaries were excellent, as were several of the supporting players.
Screenplay: 10/10 Exceptional storytelling.