The Blackwoods had been a prominent, though not particularly well-liked family in the small New England town where the story is set. Several years ago, most of the family was killed via arsenic-laced sugar they had sprinkled on their fruit at dessert. The only survivors were Constance, the sweet-natured older daughter who never took sugar on her fruit, Uncle Julian, who only ingested very little and was incapacitated for life as a result, and Mary Katherine (or Merricat), the younger daughter, who had been sent to bed without dinner that night.
Constance was assumed to be the culprit, but she was acquitted after a lengthy trial. Since then, the sisters and Uncle Julian have remained barricaded in their isolated mansion, the object of the townfolk's scorn and derision.
The story is narrated by the now 18-year-old Merricat, who is CLEARLY the real murderer. This was obvious from the first paragraph, where she confesses to wishing she was a werewolf and having an affinity for poisonous mushrooms. She is an unpleasant, petulant, strange young woman who obsesses over the charms she has put on the property to keep everyone out. She ruminates about how cruel her family was to send her to bed without dinner that night, and has no remorse at all for her multiple murders.
Meanwhile, Constance spends much of her time trying to avoid goading Merricat in any way - coming across as alternatively devoted and terrified - and Uncle Julian is a doddering old man with an exceedingly tenuous grasp of reality. The book wallows in the day-to-day life of these three unlikeable characters until a visitor appears and throws everything into disarray. Cousin Charles is a slimeball who has designs on marrying Constance as a way of accessing the family fortune. Merricat does not appreciate this, and crossing Merricat is a very bad idea.
I don't know. I have never much liked gothic fiction - it makes me feel claustrophobic and misanthropic. The characters feel like exaggerated malformations, and reading these books feels unpleasantly like gawking at a freakshow. I wasn't charmed by Merricat's quirks, as I think the book wanted me to be? And I never once thought anyone but she murdered the family, so the big reveal late in the book was completely anticlimactic.
Still, there was something... memorable about this story. The creepy secluded mansion felt very real, and the sneering townspeople were, oddly, some of the few characters that actually rang true to me. I read that Shirley Jackson based this milieu on the provincial, anti-intellectual town where she lived and felt like a pariah, so perhaps that is why these are the only elements that felt really authentic to me. But there is an emotional truth buried deep there, under all the tedious gothic trappings, and when it showed through - it gleamed.