There will be blood and plenty of it by the end of Emma Cline’s California-set debut, which is loosely based on the Manson “family” and their crimes. But first, ketchup. The linguist Deborah Cameron tells a story in The Myth of Mars and Venus about a family dinner. When the daughter says to the mother, “Is there any ketchup?”, the mother replies, “Yes, it’s in the cupboard.” But when the father says to the mother, “Is there any ketchup?”, the mother gets up and fetches it for him. It’s a scene that’s less about condiments than it is about power, and who is entitled to ask for what of whom. Both father and daughter make demands of the mother, but only the father gets his met.

Such interactions can easily be overlooked or ignored, but they’re the essence of social control. In order to build the case against Charles Manson (who was not present at the killing of Sharon Tate, Jay Sebring, Wojciech Frykowski and Abigail Folger), prosecutor Vincent Bugliosi had to form a picture of Manson’s domination over his followers, introducing testimony about dozens of incidents demonstrating that, whatever Manson said, his followers intuited his designs and saw them through. Commissioning a mass murder was as simple and subtle for Manson as requesting a bottle of sauce.

Since then, accounts, both factual and fictional, of Manson and the family have understandably focused on the extreme: the surpassing violence, the sensationalist coverage, the overwhelming bizarreness of the white-supremacist preacher and his female acolytes. But Cline’s fictionalised version forces us, grippingly, to look at the smallness and ordinariness underlying the family’s extraordinary crimes. A perceptive writer with a fine pen, she understands the intimate coercions that go on within every relationship, and represents them with a Katherine Mansfield-like exactness.

In the present, Cline’s protagonist and narrator, Evie, is an outsider, invisible. But in her teens during the late 1960s (flashbacks to which make up the meat of the novel), what she wants most of all is to be noticed. Like the girl in the ketchup story, her mother is unresponsive, and her unfaithful father not even in the category of people she can ask things of. Evie’s future holds little but the grim prospect of becoming a woman, which looks vividly unattractive in the closest available example: “The nearness of my mother’s distressed face, her naked upset – it stoked a biological disgust for her, like when I smelled the bellow of iron in the bathroom and knew she had her period.”

Finding Suzanne seems like the answer to all this. Suzanne, whose “face answered all its own questions”. Suzanne, a little older than Evie but living an unimaginably different life as part of a cult led by the magnetic Russell. Suzanne, who occasionally sees Evie in the way that Evie longs to be seen. “Girls are the only ones who can really give each other close attention, the kind we equate with being loved,” says Evie. Love is an act of vision in this novel: the symbol that the cult draws, in paint and eventually in blood, is a heart fringed with lashes like an eye. Not the sign of a black mass, but “just a heart, like any lovesick girl might doodle in a notebook”.

That heart is a mark of Cline’s most drastic remodelling of the Manson mythos. In the real-life Manson murders, his followers daubed “PIG” and “HEALTER SKELTER” at the crime scenes – references to Manson’s Beatles-inspired apocalyptic theology which held that a race war (“Helter Skelter”) was coming in which the blacks would overpower the whites (the “pigs”). The murders were intended to frame the Black Panthers and kick off a cycle of race violence. By excluding that, Cline also excludes some of the most troubling social history around Manson, and one of the clearest signs that the hippies of Haight Ashbury could be deeply reactionary at heart.

Including this would presumably have made it harder to sympathise with the girls. What Cline wants most of all is for us to have sympathy, to understand how girls could commit such shockingly unfeminine crimes. The answer, suggests Cline, lies paradoxically in the specific indignities of girlhood – the dehumanising demands of men, the casual violence with which those demands are enforced, the constant “campaign for her own existence” that every girl will eventually be defeated in. “Hatred was easy,” says Evie. “There was so much to destroy.” Taut, beautiful and savage, Cline’s novel demands your attention.

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