Autofiction is usually accompanied with disclaimers and explanations, shame and caveats. Caroline O’Donoghue’s new novel The Rachel Incident (Knopf; 304 pages), too, is bookended with disclaimers. It opens with, “It was never my plan to write about any of this” and closes with the protagonist saying, “It’s not my story.” Though it is unclear how much memoir this confessional novel actually holds, this conceit of autofiction is marvelously executed—the details of memory feel preciously excavated, the plot clicks in place in that inevitable way of real life. Even at its most alarming—the protagonist extorts an older couple to fund her abortion, perhaps rightfully so—the narrative proceeds realistically. Perhaps because of the novel’s tone of hindsight, every strike of calamity possesses simultaneously the sense of panicked devastation and of self-inflicted pathos. We know everything works out okay (the narrator is a professionally busy and married pregnant adult), but we wonder how everything worked out okay. The protagonists mature and grow up in a business-like way; their character arcs are straightforward, necessary, propulsive. Maturity accumulates indiscernibly, like real life. The narrative never loses pressure, fuming with the eye-watering anxieties. Best of all, it is hilarious throughout.

In The Rachel Incident, a journalist looks back on 2010, a pivotal year of her life: “I was twenty and I needed two things: to be in love and to be taken seriously.” It is the beginning of a lifelong and life-changing friendship with James Devlin, a working-class closeted gay man. “ ‘Listen,’ he said, as if he were about to lay down an important house rule, like no shoes on the carpet. ‘I’m camp as a row of tents, I know that, but I’m not gay.’ ” Rachel is spit out into the Irish job market during a global recession and must navigate the bothersome fact of money. She experiences a formative romance—“But this was not lying on my bed while a boy fidgeted about, my breasts getting cold as my mind became full of errands.” Efficient but vividly evocative sentences like this fill the novel.

Most importantly, Rachel gets entangled with an older couple, the Harrington-Byrnes. (Her retrospection is triggered by finding out the husband is in a coma.) James, her best friend, begins an affair with this husband, her professor, while Rachel begins working for the professor’s wife. After the affair is found out, the husband implicates Rachel instead of James, since the professor is closeted. “I have read a lot of books about the lasting trauma of young women and their dastardly, corrupt English professors and what happens when they fuck you,” the narrator says. “I have read nothing whatsoever on the trauma of when your English professor decides not to fuck you.” Through frank, sincere, and steady examination, Rachel reveals the machinations that burst into “the Rachel incident”—her small town’s false impression that she had an affair with her professor.

There is a rustling of cultural analysis throughout O’Donoghue’s novel: “I had read about the Bloomsbury Group, and Paris in the 1920s. But despite all that I was blind to the emergence of a scene when it was happening right in front of me. I never considered that the bands I saw, the things we wore or the people we slept with were the edges of a larger circumference, the makings of a circle.” She notices the fashion colors of the decade, the music, the entertainment, and the economy. The book is partly about Irishness: “Perhaps it’s because so many people claim Irishness that we keep putting our private jokes on higher and higher shelves, so you have to ask a member of staff to get them down for you.” The most oppressive specter in the novel, however, is money. “So many of my beliefs about the world had been predicated on our once having had money.” She says about the older couple: “In my head, Deenie was rich. She was in her thirties and she had nice clothes and a nice house. Surely if her mother was broke, Deenie wouldn’t live so well. I didn’t understand, then, that having extra at the end of the month to spend on pastries and wine is not the same as having a mother who can retire. One was a matter of hundreds, and the other was thousands.”

Except for Rachel, there is a seductive opacity to all the characters. Rachel admires them, resents them, learns from them, understands them—but she never sees through them. This makes for true surprise and misunderstandings, leading to confrontations and revelations. She is taken aback by James’s affair with her professor; she is confused by her boyfriend, and she is shocked by the professor’s choice to implicate her as his lover. The characters are, in a final sense, intensely observed but inscrutable. There is a satisfying parallel between how characters compete for space in the novel and how loved ones compete for our emotional bandwidth. Her boyfriend accuses her of being too codependent with James, and she feels torn between empathy for the wife being cheated on and the cheating husband. At one point, she observes: “Deenie kissed him, getting up on her tiptoes to do it, and said she’d see him at the pub. I felt annoyed by the tiptoes, the gauche expression of tiny-ness from her.”

The Rachel Incident is sometimes perplexing with its unnecessarily attention-grabbing prose: “By the sixteenth ‘Cecilia,’ James and I had given birth to our relationship and it wandered around the house like a sticky, curious foal.” She describes the depressing sex with her first boyfriend as: “I was always on top, moaning away like a stuck pig.” Her boyfriend is “harder to pin down than egg whites.” She says: “Our love had short fingernails. It was clawing and mischievous and it wrapped us in spit.” But sometimes the prose is precise, lucid: “We moved through the motions like people after a funeral, with a sense that, even in the worst situations, people still need to be fed and get places.” When the wife finds out about the affair and breaks down, “She started aggressively swiping at her tears, like she was trying to take off some of her skin.” And when Rachel breaks big news to James, “He walked around the room in a circle and sat down. Then he got up and did the same thing again. He looked like a dog who couldn’t settle.”

The novel’s most memorable moments are of exhausted, unfiltered honesty: “Dr. Byrne and I looked at each other. It was impossible to believe that he had once been my mysterious and beloved professor … I felt now like we were two sad clowns in a nursery painting.” That is what the book sinks into—wanting to be loved, being thrilled when you are loved, being lonely when you are not.