The title says it all upfront there is hardly any more direct a way you could refer to a film about possession than calling it demon. This leads you to certain expectations before you sit down and watch it. These also are expectations that Marcin Wrona ends up considerably undercutting. One of the most glaring of these is that despite the title Demon, the film does not actually feature any demons. It does feature a dybbuk, which, according to Jewish folklore, is the disembodied soul of a dead person.
Of course, the other expectation that a film titled Demon gives you is part and parcel of the whole exorcism and demonic theatrics sideshow that has taken over the genre since The Exorcist (1973) the head-turnings, vomitings, people mouthing obscenities and taunting others with personal information, the levitations, the cracked and sore-ridden faces, the priests standing over chanting the power of Chris compels you and so on. Marcin Wrona concerns himself with none of that. At most, Itay Tiran goes into convulsions during the middle of the wedding dance and is shuffled away to the cellar where he proceeds to talk in foreign languages and a girls voice. There is a priest present, as well as a doctor and an aging Jewish man who specifically states that he does not have enough knowledge to be a rabbi, and all seem to have a different opinion about what is going on.
Demon is a film about possession that is remarkably free of the usual horror cliches and claptrap about possession and exorcism. Instead, Marcin Wrona makes it a film centred around a situation the wedding and how Itay Tirans increasingly strange behaviour upsets what is going on. He is locked in the cellar but less for the usual reasons of chaining the demon up than simply that the father-in-law (Andrzej Grabowski) wants to sweep under the rug the embarrassment that his behaviour presents in front of the gathered guests. Much of the middle of the film is taken up not by an exorcism but by the sometimes comical interactions between various guests.
This leads to the striking ending. Where a standard Western possession and exorcism film climaxes in a furious battle for the soul of the person inside the possessed body, Demon simply has Itay Tiran escape from the cellar we dont even know where he ends up going after that point despite a manhunt instituted for him, or what his eventual fate is. Rather Marcin Wrona is fascinated with what the possession represents namely the dead of the Holocaust coming back to haunt modern Poles. In a truly remarkable ending, father-in-law Grabowski stands up before the wedding party and makes a speech suggesting that what they saw didnt happen, that it was a collective illusion. The end of the film shows bulldozers demolishing the house and barn where the wedding took place. In other words, this is Marcin Wrona tackling the collective denial that modern Poland seems to have about the Holocaust the rejection that they were party to handing the Jews over to the Nazis to be slaughtered, the erasing of this past and even demolishing of many of the Jewish ghettos. The buried guilt, Wrona seems to be saying, lurks and continues to haunt the modern world.