History Film / ISawTheDevil

** Even the despicable serial killer Kyung-chul evidently has people he cares for [[spoiler: as when he hears the voices of his abandoned elderly parents and young son (that he seemed to take efforts in keeping separate from his crimes) trying to visit him while he's trapped in a guillotine he begins to genuinely panic and frantically begs them to leave so they won't have to see him gruesomely die. It's quite harrowing and one of the actions that solidifies Soo-hyun's descent into a monster.]]

* CautionaryTale: [[spoiler:Throwing all caution to the wind and giving into the darkest depths of your desire for revenge]] can leave many others injured, traumatised, or ''worse'' in your wake, [[HeWhoFightsMonsters and the cost to your own life may be greater than you could ever predict.]]]]

* TearsOfRemorse: Soo-hyun sheds these at the end. While probably not regretting [[spoiler:killing Kyung-chul]], he probably regrets [[spoiler:the things he did to get Kyung to where he wanted him and that he's become just as bad as he is]]. But by the time he realizes that, it is too little, too late.

* WhatHappenedToTheMouse: What happened to the schoolgirl and the kidnapped victim in the cannibal's house? We see them scurry away as Soo-hyun battles Kyung-chul, but there's no follow up. One can presume that the police took care of the latter.

''I Saw the Devil'' is a 2010 South Korean {{revenge}} action-thriller film directed by Kim Ji-woon (''Film/ATaleOfTwoSisters'', ''Film/TheGoodTheBadTheWeird'', ''Film/ABittersweetLife'') and starring Creator/LeeByunghun and Choi Min-sik.

* AintTooProudToBeg: Double subverted. [[spoiler:When Soo-hyun finally gets Kyung-chul exactly where he wants him to execute his final act of revenge, he seemingly breaks down and begs for his life, but then drops the act and states that since he cannot feel pain or fear -- the exact things Soo-hyun wants him to feel the most -- Soo-hyun's work is AllForNothing. However, once he leaves Kyung-chul holding up his own guillotine blade by a rope in his teeth that connects to a door, his family arrives and starts to open the same door, at which point he begins letting out very real, very terrified pleas for them to leave. [[HoistByHisOwnPetard It]] [[OffWithThisHead doesn't boot.]]]]

* CaughtWithYourPantsDown: When Soo-hyun drops in on his first suspect, he's busy masturbating to porn in his room. He decides to alert him of his presence by cutting his computer's power just as he's about to finish.

* DevilInPlainSight: How Soo-hyun sees Kyung-chul. The title, which explains it all, is considered an ironic coincidence in that [[spoiler:his sadistic acts turn him into a Devil-like figure himself come the end]].

* DownerEnding: [[spoiler:Soo-hyun manages to see to the end of his retribution against Kyung-chul, resulting in his death, but by this point, it's clear he's lost everything. His career as a police officer is in jeopardy because of the sheer amount of damage he's caused in his pursuit of vengeance, his father-in-law ends up grievously injured, his sister-in-law ends up ''dead'', and in having Kyung-chul decapitated [[KickTheDog right in front of the guy's parents and son]], he realizes that he [[HeWhoFightsMonsters has become just as monstrous as Kyung-chul had been]]. By the end of the movie, he's walking away from all the carnage he's caused, crying hysterically, completely alone.]]

* PyrrhicVictory: [[spoiler:Soo-hyun may have gotten his revenge by murdering Kyung-chul, but he ends up causing huge amounts of damage, including his father-in-law being grievously injured and his sister-in-law being killed. Never mind the fact that he also [[HeWhoFightsMonsters becomes]] [[EvilvsEvil just as monstrous as Kyung-chul was in his pursuit for vengeance.]]]]

* TearsOfRemorse: Soo-hyun sheds these at the end, while probably not regretting killing Kyung-chul, he probably regrets the things he did to get Kyung to where he wanted him and that he's become just as bad as he is. But by the time he realizes that, it is too little too late.

* AttemptedRape

* PyrrhicVictory: [[spoiler:Soo-hyun may have gotten his revenge by murdering Kyung-chul, but he ends up causing huge amounts of damage, including his father-in-law being grieviously injured and his sister-in-law being killed. Never mind the fact that he also [[HeWhoFightsMonsters becomes]] [[EvilvsEvil just as monstrous as Kyung-chul was in his pursuit for vengeance.]]]]