A man is knocked unconscious by a booby trap. Not graphic.
There are many disturbing/upsetting images in the films first two acts, but the actual violence does not occur until the films last 30 minutes. Past that point, the violence is graphic and relentlessly brutal.
A woman is seen to have killed herself in her bathtub. It is filled with blood and her brother mourns over her lifeless corpse.
A little girl drowns in a river. Her dead body is seen sinking then floating onto a rock where her eerily lifeless corpse stares directly into the camera. Her corpse is shown being dissected with a scalpel with blood seen while it cuts, and then when the camera turns away we hear graphic sounds of medical procedures while her horrified father watches. There is also another scene of medical dissection in the film that shows no more than this scene.
The tone of this film is much bleaker and the imagery is more realistic than any of Park Chan-Wook's other films including Oldboy.
Most brutal out of the Vengeance Trilogy, but not the most graphic in terms of imagery. This film does have the most unflinching amount of brutality though.
A few scenes of brutal and bloody violence.
A man's neck is stabbed with a screwdriver. When the screwdriver is ripped out blood starts squirting and oozing out. We see him dead on the floor with a massive pool of blood surrounding him.
There is a brutal torture sequence where a woman has clips attached to her ears and she is shocked for over 20 seconds to force her into talking. She is heard screaming in agony, and then she begins urinating on the floor and twitching at her feet. Despite already being close to death the torturer starts electrocuting her again. Later, we see that she is dead with an image of her fried ears and her pale corpse.
A man is smashed on the head with a bat, dragged on the floor and then has his head viscously smashed over and over again while he lays unconscious. Blood starts pouring out onto the floor as the killer brutalizes the body, but the scene cuts soon after. His corpse along with others are seen shortly after with loads of blood everywhere.
Bloody bags and clothes are then seen, implying that a dead man is being dismembered for burying.
Morticians perform an autopsy on a dead girl, we hear her body cracking. We then see her burning hand while she's being cremated.