The Shampoo Effect
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Jenny Jackson on The Shampoo Effect
In her own words: quotes and insights from the author.Why she wrote it
Two scandals, one novelThe book’s premise began not with a plot idea but with a lifelong piece of local lore. Jackson grew up in Ipswich, Massachusetts, knowing that John Updike’s 1968 novel ‘Couples’ had detonated his own friend group, ending marriages and burning social ties. That story followed her into adulthood and then into the office, when she took a job at Knopf, the very house that had published Updike. The convergence of personal geography and professional history made the question of what art costs the people closest to a writer feel unavoidable.
I grew up hearing this story, and then, as an adult, I took a job as an editor at Knopf, Updike’s publisher. I became intrigued by the idea of him, a writer in a small town, mining his social set for material, and the way making art might lead to betrayal.
A second, far less literary scandal completed the spark. Tom Brady’s mid-2000s love triangle, with an unexpected pregnancy overlapping a new relationship, handed her a plot that was essentially pre-built: an outsider, a tight-knit community, a secret that reorganizes everything. Neither the Updike story nor the Brady story was enough alone, but together they gave her the architecture.
So these two gossipy scandals tangled together in my mind to become a novel.
Her craft essay in Lit Hub also names what made gossip itself the right engine for the story: “Gossip is a wonderful barometer of storytelling. If you find yourself hanging on every word of a whispered story, chances are the reader will too.” The form and the content arrived together.
Once she had the premise, she also had a personal reckoning to embed in it. After ‘Pineapple Street’ placed her in readers’ minds as a chronicler of wealthy Brooklyn, she wanted to correct the record. She was not from that world, and she had been satirizing it.
I’m not a one percenter, and I didn’t grow up in New York. Part of writing ‘The Shampoo Effect’ for me was subconsciously a corrective to write about my hometown and where I’m from.
How she wrote it
Hermit mode and a restructured romanceThe writing schedule for ‘Pineapple Street’ had been unusual by any measure: COVID lockdowns, no commute, 4:30 a.m. starts, a sustained sprint. ‘The Shampoo Effect’ demanded something structurally opposite. With two children in school and a full editorial job, she wrote in four-day isolated chunks whenever her husband could take the kids away, and compressed additional time into school holidays.
I walked to ‘Pineapple Street,’ not [with my] knives sharpened, but I was ready to make fun of those characters. With ‘The Shampoo Effect,’ it’s not as satirical. I love these characters and all of their foibles.
That emotional shift had a practical cost: she threw out more material. Scenes that were accurate to who the characters were but that didn’t move the plot forward had to go, even when they had taken real time to write.
The structure she chose, rotating close third-person narration, was the same one she had used in her debut, but she has a specific theory about why it fits the kind of story she wants to tell. Van, the man at the center of the love triangle, never gets his own interior chapters in ‘The Shampoo Effect’: he exists only as others see him, which is itself an argument about how intimacy works.
I love, love, love to write in a close third-person point of view that rotates. I think for me it’s because when you’re writing from different perspectives, you have the chance to explore misunderstandings, you have the chance to explore the ways in which really good people with good intentions can totally mess up and get crossways. And so I’m not interested in writing about big villains... I’m interested in writing about decent people who misunderstand one another, who want different things and who have to figure out how to be their best selves. [paraphrased from audio]
One early structural decision cost her an entire revision. Having sat through TV pitch meetings after ‘Pineapple Street’ and absorbed the standard note that action should front-load, she revealed the pregnancy at the top of her first draft. Her editors pushed back, pointing out that readers had no reason to care about the couple before the disruption landed. The lesson she drew was simple and direct.
I was like, ‘Oh, right. Writing for a book is different than writing for TV.’ [paraphrased from audio]
The personal thread
The friends she almost stayed withThe novel’s emotional center came from a private fantasy Jackson has carried about her hometown: what life would have looked like if she had stayed in Ipswich and raised her children alongside her oldest friends instead of building a career in New York. The fantasy is warm but not simple, because those friendships have quietly diverged over decades.
You know them on a level that you will just never know a friend that you make in adulthood. Like, I have never seen what my other friend’s parents wear to bed, or used their mom’s shampoo…Those childhood friendships actually imprint on you.
The title of the novel, ‘The Shampoo Effect,’ is her phrase for the way long-term relationships resist being fully washed out, even when circumstances change completely. She arrived at it by way of a literal memory: borrowing a friend’s mother’s shampoo as a child, and the way that smell became attached to something larger than itself. The explanation she gave the Boston Globe turns the metaphor into a theory of how love persists.
It’s a hangover phenomenon. It’s like the hair of the dog. But, for me, it’s about how some things never really leave your system, or you’ve become so immersed in something, that if you’ve always loved someone and situations change, you’re still going to have that love for them. It’s about the way that these long-term relationships are really just never going to fully wash out.
On what the book is wrestling with
Friendship’s conditional stakesThe novel’s central disruption, an unexpected pregnancy that lands in the middle of a friend group rather than a marriage, gave Jackson a way to test how conditional even the deepest friendships are. She had already written about family, where the bonds are structurally unconditional. Here she wanted the higher-stakes version: relationships that require ongoing choice.
I think that we’ve all come to understand that a baby is a bomb that goes off in the middle of a marriage. But what happens when there’s no marriage? It’s a bomb that goes off in a friend group, and it catches everybody in the shrapnel.
The book is also an argument about what diverging adult paths do to people who once moved in lockstep. When old friends make different choices about careers, children, or where to live, Jackson identifies a specific emotional residue that rarely gets named.
I think on some level that starts to create little feelings of friction, and I’d also go so far as to say betrayal in old friendships. You just feel like, hey, why is my friend not making the same choices that I am? Am I doing something wrong? Are they doing something wrong?
The book’s argument about friendship ultimately lands as an ethical one. Conditional bonds, Jackson suggests, are not weaker than unconditional ones. They demand something specific from the people inside them.
part of having these strong, long-term friendships is being caring and really nurturing those friendships in a way that you don’t have to nurture some of your other relationships. So I think that having these conditional and yet really intimate friendships makes us all better people.
What she wants us to sit with
Good people, unresolved endingsThe book presents itself as a coming-of-age story, but Jackson is specific about which coming-of-age she means. She is not interested in adolescence. She is interested in the quieter, more disorienting versions that arrive in your thirties and forties, when the life you chose has drifted from the life your friends chose, and you are not sure whose version is right. Parenthood, she argues to the She Writes interviewer, is the experience that makes this crisis legible.
One of my favorite dinner party topics is to talk about how old you feel on the outside vs. how old you feel on the inside. I personally feel 40s on my outside and about 30 on the inside. Until I had kids I would have told you I felt 22 inside. That’s the thing about becoming a parent—it forces you to play the role of adult, but it doesn’t mean you necessarily feel that way inside.
Resolution in the book is partial by design. Some characters have forgiven each other by the final pages and some have not, and Jackson has been explicit that she considers that the honest version. Her intention in the Open Book with Jenna interview was stated plainly as a refusal to assign moral verdicts.
No heroes or villains. That’s not my thing. I want good people who mess up and try and do better. [paraphrased from audio]
The mess, she has said, does not preclude joy. She told Reader’s Digest that she tries to infuse her books with joy regardless of the friction inside them. The two coexist, and she considers that coexistence the point.