It is apparent that British author Ian McEwan set lofty goals in piecing together his newest novel, Sweet Tooth—goals that he has accomplished in novels past, but lofty ones nonetheless.

Memory and imagination are recorded in the mind in tandem, influencing one another as they solidify. Sweet Tooth tells the story of a beautiful British spy who betrays her mission in favor of romancing her subject. Touching the psychology of deception, the novel suggests that fiction and reality are estranged but rival brothers, born of the same blood line, but competing for which will leave a more enduring legacy. The theme invokes McEwan’s 2001 masterwork Atonement, in which another youthful and deceitful female narrator introduces herself as infallibly clever—though the reader learns otherwise—and comes to such realizations about the limits of lying. But Atonement does it better.

Serena Frome (rhymes with “plume,” she specifies in the opening sentence of the novel) recently graduated from Cambridge with very poor marks and a degree in mathematics. It’s 1972, and the Cold War is raging. But unlike her flower child sister, Serena has her mind on selfish endeavors. She cycles through romances with strange men at what seems to be her own insatiable whim and is quick to gloat about her ability to beat even the most confident men in a round of chess. All the while, Serena claims to devour three or four novels per week by merely glancing at each page. She follows the storylines of strong female characters who, much like herself, meander in and out of love rather than absorbing the novels’ themes and descriptions.

Her reading habits provide a stark contrast to the way in which McEwan treats his audience. Sweet Tooth, like all of McEwan’s works, slips in details that are gems worth digging for, as they surprisingly help the reader later in the story. Serena takes subtleties like these for granted, perhaps explaining why she so easily falls prey to a character who closely resembles McEwan himself.

A self-proclaimed possessor of both beauty and brains, she is recruited for M15—the domestic branch of the UK’s intelligence system—by Tony Canning, the middle-aged, married history tutor with whom she had an affair at the tail end of her Cambridge career. Despite her shaky performance as a math student and her detached devotion to literature, Canning sees Serena as an ideal candidate for the British intelligence agency in the heat of the West’s engagement with its Communist opponents (she had a brief stint during which she wrote anti-Soviet diatribes disguised as book reviews in a Cambridge periodical).

Her mission, “Sweet Tooth,” aims to create a foundation to fund and support budding authors whose literature serves the needs of the state, thus maintaining anti-Soviet sentiments in England. Serena is swept up to the University of Sussex, McEwan’s alma mater, where she is sent to spy on and follow Thomas Haley, a doctoral candidate in literature. Haley is the author of several lesser-known short stories and journalistic works, which, upon commencing her mission, Serena reads hungrily. McEwan dedicates a large chunk of his novel to Serena’s recounting of Haley’s literature, some of which very closely resembles a couple of the short stories McEwan published at the beginning of his career.

The spy falls in love with her subject’s stories, attracted to their clean portrayals of life. Then she falls in love with Haley himself, prompting Serena to partially depart from her duties as an MI5 employee. Out the window goes her dedication to country and her motivation for anti-communist escapades. It is at this point that the reader has his suspicions confirmed. Serena truly is self-serving, deluded and unreliable—McEwan’s defective narrator is an embodiment of his assertion that stories, even when claimed to be true, must be taken at face value.

Although Sweet Tooth’s backdrop works to remind the reader of Cold War-era Britain by painting details like the IRA bombings and England’s unstable government, these realities fade to dark almost as soon as Serena and Haley fall into bed together. Under Serena’s watch and subsidy, Haley publishes a novel that gets nominated for a literary award, hinting that operation “Sweet Tooth” may be succeeding. But as the relationship intensifies, Serena loses her grip on the mission, convincing herself that she never would have been able to succeed as a spy in the first place.

The novel’s plot does not come as a shock—Serena reveals on page one that she went to school, became a spy and failed her mission. It’s the ending that shakes the reader’s perception of Serena’s recollections and works to promote McEwan’s thesis that fiction and reality can be as tricky of adversaries as spy and subject. However, McEwan’s big reveal is not as jarring and poignant as it has been in his past works. A similar ending in Atonement­—one that left McEwan’s audience wide-eyed and astounded at how exactly McEwan so cleverly strung all the details together—is not quite as effective in Sweet Tooth. A recycled plot line of a spy falling for her subject and the near-insufferable naivete of the narrator make for less pop in McEwan’s latest novel.