Basically, it's horror. Oiwa was a woman that was married to a jerk named Iemon (Yay-mon), who only married due to lust. He fell out of love for his wife after the birth of their son and wanted to marry another woman from a wealthy family. He gets rat poison, mixes Oiwa's medicine with the rat poison, wakes up his wife and gets her to drink the rat poison. Oiwa drinks it and gets disfigured. She falls on one on Iemon's swords as he is a masterless samurai, which kills her. Before Oiwa's death, she knew her husband was having an adultrous affair and about the plot to kill and she vows revenge against Iemon. Iemon nails her body to a door and throws it into the river in order to marry his new wife. On his and his new wife's wedding day, his new wife's face transforms into his deceased Oiwa's face and going mad he kills her. Oiwa drives him insane so much that he impales himself on a bamboo thicket or something like that.