* AdaptationDisplacement - Some people had no idea of the folk tale until they saw this movie.
* EpilepticTrees: Wow. Where to begin?
* MoralEventHorizon - [[spoiler:A flashback at the very end of the film]] reveals that [[spoiler:Eun-ju witnessed Su-yeon being crushed by the cupboard, but did nothing to help her]].
** This is even worse considering [[spoiler:Eun-ju was ''going back'' to help Su-yeon, but decided not to ''just to spite Su-mi''.]] Yikes.
** For some, Su-mi crosses this when [[spoiler:it is revealed that she snapped Eun-ju's bird's neck. Granted, she ''is'' delusional, and she is most likely doing it out of her hatred for Eun-ju, but, still.]]
** Also, the sequence in which Eun-ju locks Su-yeon inside the cupboard that terrifies the latter so much and refuses to let her out, despite her heartbreaking screams. [[spoiler:Of course, this and any other instance of this trope is somewhat subverted once you realise that this was all in Su-mi's head.]]
* NauseaFuel: The scene in which the wife of the girls' uncle vomits whilst having a fit ([[spoiler:and possibly being possessed]]), before getting it in her hair and on her face during her spasms.
** The fish carcass in the fridge.
* RewatchBonus: Several scenes. The film usually requires a second or a third viewing to understand just what is going on, and, after the numerous revelations, almost every scene takes on a hugely different light.
* TheWoobie: Everyone - well, almost. Expect a debate about [[AlternateCharacterInterpretation whether or not Eun-ju is a woobie]].