Oprah Winfrey announced that the latest selection for her book club is Jeanine Cummins’ American Dirt, a novel that has quickly become the most controversial book of the year so far.

The controversy over Cummins’ novel, about a Mexican mother and son forced to immigrate to the U.S., began last month when author Myriam Gurba published a negative online review of the novel. The review had originally been assigned to her by a “feminist magazine,” which ultimately declined to run it.

“Cummins plops overly-ripe Mexican stereotypes, among them the Latin lover, the suffering mother, and the stoic manchild, into her wannabe realist prose,” Gurba wrote. “Toxic heteroromanticism gives the sludge an arc and because the white gaze taints her prose, Cummins positions the United States of America as a magnetic sanctuary, a beacon toward which the story’s chronology chugs.”

While the review raised eyebrows in the literary community, the controversy over the book boiled over when the New York Times published a brutal takedown of the book by critic Parul Sehgal, who wrote, “The real failures of the book, however, have little to do with the writer’s identity and everything to do with her abilities as a novelist. What thin creations these characters are—and how distorted they are by the stilted prose and characterizations.”

Shortly after that, the Times ran a review of the book by novelist Lauren Groff, who seemed conflicted about the novel, writing, “In the end, I find myself deeply ambivalent. Perhaps this book is an act of cultural imperialism; at the same time, weeks after finishing it, the novel remains alive in me.”

On Twitter, Groff expressed regret that she’d written the review at all, calling the situation a “fucking nightmare,” and writing, “I wrestled like a beast with this review, the morals of my taking it on, my complicity in the white gaze.”

The controversy doesn’t seem to be hurting sales of American Dirt, however. As of Wednesday afternoon, after Winfrey’s endorsement, the novel was the No. 3 bestselling book on Amazon.

Michael Schaub is an Austin, Texas–based journalist and regular contributor to NPR.