“Hi guys, welcome back to Book Club,” the model Kaia Gerber said with a California lilt. Seated in her bedroom in Malibu late in February, Ms. Gerber watched as thousands of viewers trickled into her discussion with the playwright Jeremy O. Harris, recovering from an all-nighter.

“It’s great to wake up and get energized hearing someone speak so kindly about you and their experience with your work,” he said.

Over the next hour, Ms. Gerber and Mr. Harris discussed the racial and sexual politics of his Tony-nominated “Slave Play,” the Reconstruction Era and the impact of President Franklin Delano Roosevelt’s Federal One arts program. At one point, Mr. Harris shared a list of Black and queer theory texts including “Mama’s Baby, Papa’s Maybe: An American Grammar Book” by Hortense J. Spillers, which Ms. Gerber promised to pass along to her millions of followers.

Like many, she began her virtual book club during lockdown last spring, discussing Sally Rooney’s book “Normal People,” with the actress Daisy Edgar-Jones on Instagram TV. The videos since have racked up hundreds of thousands of views. (In-person book events tend to draw between 20 and 200 people.)

Ms. Gerber has joined a blooming ecosystem of book clubs, “bookstagrammers,” “BookTokkers” and promotional venues (like podcasts) that did not exist a decade ago. “Over the past 10 years, we have been remembering how important it is not only to consume great books, but to talk about that consumption,” said Lisa Lucas, the publisher of Pantheon and Schocken Books. “It’s so much more obvious in a digital world, that we’re all reading the same thing.” (Or at least pretending to.)

A generation after Oprah’s Book Club changed the publishing industry, Ms. Gerber is one of several fresh-faced mega-influencers using Instagram to share literary life with millions of eyeballs. The model Emily Ratajkowski, whose essay collection, “My Body,” will be published this fall by Henry Holt, has been sharing literary fiction and nonfiction recommendations on Instagram and in interviews for several years, too. (Notably, the cover of “My Body” is text-only.)

The Grammy-nominated singer-songwriter Amerie hosts a monthly club on YouTube and Instagram, where she reaches a combined 600,000 followers. Florence Welch and her fan club have been operating the club Between Two Books since 2012.

And Elaine Welteroth, the former editor of Teen Vogue, seems to be getting into the book club game as well, promoting Cicely Tyson’s memoir, “Just As I Am,” at the end of February, which she discussed on the CBS daytime show “The Talk” and on Instagram Live.

The actress Emma Roberts started the Instagram book club Belletrist with her close friend Karah Preiss in March 2017. “It’s one of my favorite ways to engage with my followers,” Ms. Roberts said. “Talking about books just adds so much more substance to your online interactions.”

Producing Belletrist is now Ms. Preiss’s full-time job, and the company has adaptations in development at Netflix, Hulu and HBO Max. At first, Ms. Preiss said, people didn’t understand Belletrist. “Everyone was like ,‘What’s an Instagram book club?’ Instagram is on your phone,” she said.

But the format has thrived in quarantine. “Finding community in digital spaces is really what Instagram is best suited for,” Ms. Preiss said, adding that she thinks online book talks will last for those in people in suburban and rural areas. “Unless you live in a major city, you can’t go to a reading every night.”

Instagram data has shown “a significant spike” in #bookstagram and reading content during the pandemic, according to Eva Chen, the platform’s director of fashion partnerships, and it skyrockets during the first week of every month, when new titles are announced on feeds like Reese’s Book Club and Well-Read Black Girl.

Before the pandemic, influencers might have documented their escapes to luxury hotels or tropical getaways. Now many are posting escapist or socially progressive literature to engage with their fans.

“Especially in the last few years, people are using Instagram in a much more well-rounded way to show all the different aspects of their lives,” said Ms. Chen, herself an author who routinely shares snaps of young adult titles. “I stare at a screen for 12 hours a day as part of my job,” she said. “I cannot go to bed without reading or touching a physical print book.”

The Poet Wears Prada

In some ways, all this activity is like an amped-up version of the American Library Association’s READ poster campaign, which has featured more than 200 celebrities since 1987, including David Bowie, Oprah Winfrey and Ms. Gerber’s mother, Cindy Crawford. (The campaign’s director, Rachel Johnson, said the A.L.A. has had a hard time booking talent for the last few years.)

Children’s publishing “always understood that you need to make the invitation really appealing,” Ms. Lucas said, but “in adult publishing, we have to find ambassadors and do a charm campaign ourselves.”

According to Ms. Preiss, that was part of the intention behind Belletrist: “We always kind of wanted to make reading and literary life feel as sexy and aspirational as fashion and beauty.”

In return, books and authors can confer spontaneity, gravitas and other qualities to luxury brands and their avatars. On Instagram, Ms. Chen said, “authenticity is the most important thing, and a sense of realness.”

“Books are such a pure form of how we receive ideas,” Ms. Lucas said. As a result, “everyone is paying more attention to the literary world.”

On March 7, Valentino revealed nine text-only ads promoting its next Collezione Milano collection. One features a poem by Ocean Vuong, while another is a meditation by Lisa Taddeo on her Italian mother. Janet Mock contributed a manifesto of sorts, while Yrsa Daley-Ward’s ad is a prose poem.

With the campaign and other initiatives, Valentino is seeking to equate its designs with eloquence and poetic rigor. In February, the brand provided 50 scholarships to Tomi Adeyemi’s mentorship program; the poet Rupi Kaur has performed on the label’s Instagram Live, and Valentino has published other poets’ work in a chapbook.

Valentino is not the only luxury house spotlighting authors. Prada’s 2020 Holiday campaign was written by Candice Carty-Williams, and the National Book Award winners Sarah M. Broom and Ibram X. Kendi appeared in Ralph Lauren ads last year. The United States youth poet laureate, Amanda Gorman, now represented by IMG Models, has worked with Prada since 2019. Mr. Harris designed a capsule collection for SSENSE in 2020 and appeared in last fall’s “Guccifest” presentation. Uniqlo introduced a Haruki Murakami collaboration last week.

As these intellectuals become spokesmodels, professional models seem to be increasingly photographed with books. In May 2019, Kendall Jenner was seen lounging near a pool in Cannes reading “Literally Show Me a Healthy Person” by Darcie Wilder. In December 2019, Ms. Jenner was snapped on a boat in Miami reading “Tonight I’m Someone Else” by Chelsea Hodson.

Both Ms. Wilder and Ms. Hodson have said that their books sold out on Amazon after the photos circulated online. “This capitalistic boost benefited me monetarily and, if I do say so myself, her culturally,” Ms. Wilder wrote in an essay for The Outline, because it signified Ms. Jenner’s interest in “a more imperiled creative class.” Ms. Jenner has since shared a number of books online, including “How to Cure a Ghost” by Fariha Róisín.

Celebrity book mentions can also bump book sales. The author Alisson Wood, whose book “Being Lolita” was featured by Ms. Gerber and Ms. Ratajkowski, said she saw “huge jumps” in sales and her follower count, “which, for a book that’s not a best seller, that’s a big deal.”

Ms. Wood believes that this new authors-as-models and models-as-bookfluencers dynamic is a consequence of society’s growing comfort with “beautiful women to also be smart, and for smart women to also be beautiful,” she said. “Amanda Gorman is a brilliant poet, but she can also model because she’s beautiful. Kaia Gerber is gorgeous, but she’s also really smart and loves books and wants to talk about books.”

Ms. Róisín has yet to see material gains from Ms. Jenner’s photos, but is impressed that she is engaging with the issues in her book, which “is about unlearning white supremacy and patriarchy,” she said. “It’s talking about abuse and trauma, so the fact that Kendall Jenner is reading that book, and that she’s been reading it consistently, is pretty wild.” And of the supermodel’s other reading material, given to her by her agent Ashleah Gonzales?

“If Kendall Jenner is reading Lydia Davis, that’s pretty cool.”

Harry Styles at the Strand

Ms. Gonzales, too, shares “Alt Lit” reading recommendations with her roughly 78,000 followers. “If I read something I love or something that I find relatable, I’ll pop it on Instagram to share sort of in that moment,” she wrote in an email.

As for whether the photo ops with Ms. Jenner are intended to boost specific books: “Lol, no. The only intentions were for Kendall to enjoy reading them.” Still, she said, the photos’ reception “put a huge smile” on her face.

Many of these younger influencers are active literary citizens, promoting independent bookstores over Amazon and attending events in Los Angeles and New York prepandemic. Ms. Roberts said she “found out at the last minute” that Stephanie Danler was signing “Sweetbitter” at Book Soup in Los Angeles in 2016, so she “literally ran over” to get her copy signed. The two have since become friends.

Ms. Gerber maintains relationships with some authors who have appeared on her book club through text messages and FaceTime, while Ms. Ratajkowski has reached out privately to memoirists for advice while writing her essay collection, and regularly engages with authors on social media.

Courting mega-influencers now falls to book publicists. “For all my books, I start by making a huge surrogate voices or ‘bigmouth’ list of every single dream celebrity or author or influential person who I think would love the book,” said Jordan Rodman, the director of publicity of Avid Reader Press, who has promoted darlings like “Three Women” and “Sweetbitter.”

Ms. Rodman pitches influencers the same way she pitches media outlets. “I saw that Harry Styles had gone to the Strand and bought a copy of Joan Didion,” she said. “I figured he might like ‘Three Women,’ so we got him a copy and he ended up talking about it.”

The popular subscription box Book of the Month takes a different approach, brokering deals with ambassadors like Alicia Keys, Lana Condor and Ruby Rose. In 2015, the company started featuring high-profile guest judges who choose a book, share it to Instagram and write an essay about it.

Literati, a competitor, operates book clubs for influencers like the N.B.A. player Stephen Curry and Malala Yousafzai. Zando, a new start-up, plans to use celebrity and brand partners to introduce new titles.

Early celebrity attention can prime an author for a successful, or at least visible, career. Of those included in the Valentino campaign, Fatima Farheen Mirza’s book was the inaugural title at Sarah Jessica Parker’s imprint at Hogarth, while Mr. Vuong and Ms. Taddeo received several celeb nods each on Instagram.

Book sales in the United States grew 8.2 percent during the pandemic, according to NPD, the most since 2010. During this moment of “tumult and uncertainty,” said Kimball Hastings, a fashion executive who sits on the board of the National Book Foundation, “authors play the incredibly key role of articulating and clarifying it, and helping people to make sense of it.” Art and literature have “never been more necessary on some level,” he said, and who would refuse such glamorous champions?

“My advice is not toward publishers, my advice is towards people who are spreading the word about books,” Ms. Lucas said. “That’s just to please keep doing it.”