“A child of divorce turns private eye in the latest well-observed study of domestic dysfunction from Simpson. In some ways, Simpson's sixth novel marks a return to her first, Anywhere But Here (1986), which also features a teenage narrator struggling to comprehend a parental split. But the new book is more high concept, framed as a detective story about discovering the deceptions that can swirl around relationships. The narrator, Miles, is a bright LA high schooler who's prone to precocious antics like a money-making scheme selling lunches out of his locker. He's also picked up a more questionable eavesdropping habit, listening in on his mathematician mother's phone conversations after her marriage collapses and she pursues a new relationship with Eli, whose intentions and background strike Miles as questionable. With his friend Hector, he processes his confusion both artistically (via a comic book they create together) and pragmatically, befriending a PI who helps them get to the bottom of Eli's background. The setup is ingenious on a couple of fronts. First, making the tale a mystery adds a dose of drama to what's otherwise a stock plot about upper-middle-class divorce. Second, Miles' snapping to the role of secret eavesdropper and researcher underscores how alienated he is from his mother's confusion and heartbreak. Simpson presents Miles' tale as slightly comic; this is a story of teenage misadventures, after all. But as the truth about Eli emerges and Miles gets wise to reality, she shifts into a more serious register. "Everyone had secrets, I understood, now that I did," Miles explains. "With that one revelation, the world multiplied."
—Kirkus

”Simpson's latest ensnaring, witty, and perceptive novel of family life under pressure in Los Angeles mines the same terrain as her much-lauded last novel, the immigrant-nanny-focused My Hollywood (2010). Here she puts a clever spin on domestic surveillance as young Miles begins spying on his mother, Irene, a mathematician, just as fault lines begin to appear in her marriage to his father, a Hollywood lawyer. Wily Miles, the overweight older brother of twin sisters he professes to loathe yet watches over tenderly, sets up phone taps of increasing sophistication, opens e-mail, eavesdrops, and paws through drawers, aided and abetted by his friend Hector, who is highly suspicious, and rightfully so, of Eli, post-separation Irene's increasingly enigmatic and elusive lover. As they muddle through middle school and high school, Miles and Hector become an adolescent American variation on Holmes and Watson, with the help of a kind, handsome private eye, Ben Orion. They also embark on a crazy entrepreneurial scheme involving troublesome pets. Simpson's opening gambit is a "Note to Customer" from the publisher of Two Sleuths, the best-selling comic created by Miles and Hector, but she wisely uses this framing device lightly, allowing this exceptionally incisive, fine-tuned, and charming novel to unfold gracefully as she brings fresh understanding and keen humor to the complexities intrinsic to each stage of life and love.
—Booklist

”The consistently excellent Simpson returns with what sounds like a riff on Harriet the Spy: the story of a boy investigating his parents' disintegrating marriage. The coming-of-age narrative is complicated here, though, by the disintegration of the possibility of privacy in the age of Facebook, or Snapchat, or whatever we're all on now. Am I the only one hoping that the ‘stranger from Washington D.C. who weaves in and out of their lives‘ is Anthony Weiner?”
—The Millions

“Protagonist Miles's parents are separating. He and his close friend Hector begin snooping around their belongings, and eavesdropping on their conversations in what begins as innocent, childlike "detective work," but soon evolves into something more serious.”
—Huffington Post

”In Casebook, award-winner Simpson, author of five novels that expose fraying family ties, turns a child's view on a marriage falling apart. At nine, Miles snoops on his parents, hides under their bed, rummages in his mother's drawers, and eavesdrops on her conversations. Mostly he overhears things he doesn't understand. His mum is ‘pretty for a mathematician’. His dad, a lawyer, makes people laugh. He senses their marriage is in trouble. ‘Then, it happened: the permanent thing.’ The parents separate, leaving him devastated, then getting used to it. His buddy Hector's parents divorce, and over the years the two become yellow-page detectives, tracking down Miles's mother's new boyfriend, a ‘con artist of love’, making espionage a habit, replacing his mother's Xanax with Vitamin C out of worry at one point. Their story, framed as a prequel to an award-winning comic-book series they have co-authoured, has delightful comic moments, and a surprising and poignant twist at the end.”
—10 Best New Books to Read, BBC Culture

”In the opening scene of Simpson's new novel, Miles Adler-Hart is hiding under his parents' bed. He's trying to eavesdrop on his mother (‘the Mims,’ he calls her), convinced that she is having vital conversations with the moms of the other kids in his fourth-grade class to decide how much TV he will be allowed to watch. Instead, he stumbles into the breakup of his parents' marriage. Their divorce and relationships with new partners are shown through the eyes of Miles, who snoops deep into his parents' adult lives, but has limited understanding of what he discovers there. There's warm humor and deep feeling in its portrayal of the vulnerability and messiness of family life.”
—Page-Turner: Books to Look Out For, New Yorker

”In ‘Casebook,' Simpson tells the tale of a young boy who endeavors to find out the secrets behind his parents' failing marriage.

I've never had an exclusive relationship to a room where I write. I used to want one. In my 20s, I'd look up and see the windows in New York and think of the apartments left empty all day by their owners who went to work in offices. ‘I need an office!’ I thought. I could have used one of those empty rooms.

In my 30s, I wrote in the back house of a ramshackle Spanish Revival we rented across from the ocean in the Santa Monica Canyon. I wrote thousands of pages there, but in order to see another adult human being I had to steal out through the brambly side of the house, along the driveway down to the street. I was usually spotted by my child, who was still young and would cry for me.

When I started writing ‘Casebook,’ I needed to be watched while I worked. I'd rented an office but I was recently divorced and traveling too much for a family illness. I thought that I could hold it together for a day's work if other people were around. I wouldn't let myself cry in public. I wrote the first draft on a table in the Santa Monica Public Library.

Now I write at home. I revised the last 11 drafts, red-penciled the copy editing and marked the first-pass galleys at different places in the house; sitting on the floor next to the heating vent, on my bed, at the kitchen table, leaning back in my chair with my feet up on the desk.

Writers collect stories of rituals: John Cheever putting on a jacket and tie to go down to the basement, where he kept a desk near the boiler room. Keats buttoning up his clean white shirt to write in, after work.

Instead of a dedicated room, my best trigger is the actual habit of reading over the texts from the day before. Marking. Changing. Fussing. This ritual amounts to a habit of trust. Trust that I can make it better. That if I keep trying, I will come closer to something true.”
—Writer's Room, The New York Times Style Magazine

“With best bud Hector, Miles plays amateur spy in a touching tale of teens trying to make sense of their parents' marriages and divorces. But tapping telephones and intercepting notes just might lead to more than the boys can handle.”
—New Book Picks, Good Housekeeping

"A new novel from Anywhere But Here writer Mona Simpson is big news. We're psyched for Casebook, the story of an unraveling family that asks: How much do snoops really want to find?"
—What We Love About April, Marie Claire

"Mona Simpson has a novel out full of unforgettable characters the likes of which only one of our best writers can create? April sure is shaping up to be one of [this year’s] most important months for literature."
—10 Must-Read Books, flavorwire.com

"Mona Simpson has always written movingly about young characters, from the protagonists of her early stories “Lawns” and “Approximations” to Ann in her debut novel Anywhere But Here. That makes Casebook a return of sorts: narrated by a boy who begins spying on his parents, only to discover more about them, and the family, than he ever thought he would. And yet, Casebook is a departure also—looser, edgier, with a vivid conditionality. 'I was a snoop,' her narrator, Miles Adler-Rich, tells us, 'but a peculiar kind. I only discovered what I most didn't want to know.'"
—LA Times Spring Arts Preview