“All happy families are alike; every unhappy family is unhappy in its own way.” This first line from Tolstoy’s immortal “Anna Karenina” is frequently on the mind and lips of the narrator of “The Dinner” by Herman Koch. “The Dinner,” published to international acclaim (and revulsion) in the Netherlands in 2009, has finally reached the States, and our calloused palates are now being challenged by its dry and acid taste. Not rich and delicious like Gillian Flynn’s “Gone Girl” (to which “The Dinner” is frequently compared), “The Dinner” is rather sour and unforgiving. Nevertheless, it is a delight and a necessity to read.

“The Dinner” is the story of two families, each unhappy in its own way. It is set in an offputtingly fancy Dutch restaurant, the kind of place in which it takes months to reserve a table. The diners are two couples: Paul and Claire Lohman, Serge and Babette Lohman. Paul is a retired high school teacher; Serge is a successful politician. The two are brothers. The two are enemies.

Paul and his wife Claire arrive first. The reader immediately finds sympathy with Paul’s longing to eat in the unassuming dive across the street. Paul is a lovable sort of misanthrope, critiquing everything from the food (“The first thing that struck you about Claire’s plate was the vast emptiness. Of course I’m well aware that, in the better restaurants, quality takes precedence over quantity, but you have voids and then you have voids”) to his brother. Serge is big, charismatic and gregarious — the sort of politician who would adopt an African child to further his political career (literally). His wife Babette, who arrives with red and blotchy eyes, fresh from crying, is quiet and subdued. Ever the political wife, though, Babette puts on a happy face.

As the diners traverse a pretentious five-course meal, from aperitif to digestif, any façade of happiness begins to fade. The four are there to discuss a family problem. Each family has a son, and both sons were involved in a disturbing crime. What should be done? How will it affect the boys’ lives? How will it affect their parents? How has it already affected their parents?

And why would two boys from good and wealthy families commit such a gruesome crime? One of the delights of “The Dinner” is that it makes you ponder, along with race and class and Dutch culture, the age-old question of nature versus nurture. Are the boys the products of middle-class angst or sociopathy born of privilege? Perhaps it is their genetics. But if it’s their genetics, their parents are not all that they seem.

The characters that we know and trust in the beginning of the novel, we grow to suspect and then fear by the end. This reversal, engineered by Paul, the least reliable of narrators, keeps the reader on the edge of his seat until the very end of the meal. Everyone has a past, a dark side, and by the time the characters are ready to order (only the fanciest) coffee, the truth is out on the table. The tastes, textures and secret spices of the novel’s final fruits are simply to die for.

Sometimes dismissed by reviewers as intentionally sickening, “The Dinner” rather makes one rethink how one would act in the worst of circumstances. It may seem sickening only because evil is sickening. It subtly tells us who is to blame when children go bad, and it also provides us with a solution to the worst of shared nightmares (even if its characters choose not to do the right thing). Short and enticing, “The Dinner” is easily swallowed but not easily digested. It’s the sort of novel that teaches you more than nonfiction, the sort of parable that leaves you examining yourself.

“The Dinner” has many messages — about race, xenophobia, class pretentions, the falsity of politics and the root of evil. Its overarching message is that evil could be right around the corner — or right across the dinner table. Genuine mental illness, ambition-driven craziness and mysterious malevolence all play a role in the novel. When Koch has the chance to reveal whether one “bad” character has a mental illness or not, he ultimately demurs and leaves the reader guessing. In the end, we must come to our own conclusions whether nature poisons nurture or if nurture corrupts nature.

“The Dinner” is a story of unhappy families. Only if Tom Riddle and Lady Macbeth got married and gave birth to Leopold and Loeb, could the Lohman family get any more screwed up. If “Life of Pi” is a book to make you believe in God, “The Dinner” is a book that will make you question basic human goodness. You will never look at your fellow diners the same way again.