Mary Katherine "Merricat" Blackwood
Merricat is the novel’s narrator and protagonist. Currently 18 years old, she was 12 when most of her family died after being poisoned. From early in the novel, Merricat acts younger than her age, smashing things when she gets upset and talking about having conversations with her cat as if he responds to her. She also practices compulsive behavior to control her world through a sort of magic—for example, she creates rules for herself to follow and buries money and other small treasures. Towards the end of the book, it is revealed that Merricat, not Constance, poisoned her family, after they sent her to bed without dinner. Merricat has thus acted violently in addition to her often violent wishes of others dying. The only people Merricat cares for are her sister Constance, who she loves deeply, and her uncle Julian (as well as her cat, Jonas.) It’s not fully clear whether Merricat has always acted in her odd manner, or if the murders affected her more deeply than she lets on.
Constance Blackwood
Constance is Merricat’s 28-year-old sister, who was 22 at the time of the murders. Widely believed to have poisoned her family despite being acquitted, Constance is a recluse who only goes as far outside as the garden. Constance cares for Merricat and Uncle Julian and runs the household, seeming to enjoy cooking and cleaning. Constance knows that Merricat is the true murderer and allowed herself to be put on trial without exposing Merricat, demonstrating her love for her sister. As the novel progresses, Constance begins to doubt whether it’s truly best for her to remain isolated, but after the fire towards the end of the novel, she fully recommits to living in isolation with Merricat.
Julian Blackwood
The brother of Merricat and Constance’s father, Uncle Julian is the only survivor of the murders other than the girls, though the small amount of arsenic he ingested disabled him. Uncle Julian is obsessed with the murders, collecting detailed information about them and often reviewing his papers out loud with Constance. Yet despite losing his wife and brother in the poisoning, Uncle Julian treats it with a cheerful tone and seems to enjoy having been a part of an infamous crime. Because the arsenic damaged his memory, Uncle Julian sometimes doubts if the murders really did happen, and believes that Merricat died in the orphanage while Constance was being tried.
Charles Blackwood
Charles is the sisters’ cousin. He initially appears saying that he wants to help the sisters, but though Constance welcomes him, Merricat is immediately hostile towards him, and he begins to treat her with similar disdain. He also quickly loses his patience with the eccentric Uncle Julian. He becomes obsessed with the Blackwood sisters’ money, exasperated at the little concern the sisters show towards it and caring only about the safe when the house catches on fire. Notably, he also treats Merricat as younger than she is, even though he refuses to play into her other delusions.
Helen Clarke
Well-meaning but naive, Helen Clarke is Constance’s only link to the outside world at the start of the novel. Compared to the other characters, Helen Clarke is surprisingly rational, though she does underestimate the threat that the villagers pose to the Blackwoods. Merricat’s hatred of her underscores Merricat’s own irrationality.
Jim Donell
A villager and the chief fireman, Jim Donell viciously hates the Blackwoods and is seen tormenting Merricat in the first chapter. He does put out the fire in the end, but also leads the villagers’ attempts to destroy the Blackwood home.