If you loved Clay's journey to uncover the secrets behind Mr. Penumbra's quirky bookstore, you'll adore The Storied Life of A.J. Fikry. Here, A.J., a curmudgeonly bookseller, embarks on an unexpected quest for meaning after a rare book is stolen—and a mysterious package appears. Like Sloan’s novel, Zevin’s story is driven by the pursuit of a puzzle, set deep in the heart of book culture, and full of surprises along the way.

If you enjoyed the eclectic cast at Penumbra's bookstore—from the enigmatic Penumbra himself to the inventive Kat and the loyal Mat—you’ll love The Eyre Affair. Literary detective Thursday Next is surrounded by a wild, unforgettable ensemble: book-jumping villains, quirky coworkers, and literary figures come to life. Every character adds a dash of wit, wonder, or weirdness, making the story a true delight.

Just as you laughed at Clay's fish-out-of-water adventures in the mysterious world of Penumbra’s, you’ll grin through The Rosie Project. Don Tillman, a genetics professor, approaches romance the way Clay approaches puzzles—analytically and with plenty of unintended hilarity. The book’s sharp dialogue and gentle satire make it a fun, uplifting read.

If you were fascinated by the intersection of old-school mystery and high-tech puzzles in Mr. Penumbra’s 24-Hour Bookstore, you’ll savor Sourdough. Lois, a software engineer, is drawn into a secret society of bread bakers in San Francisco, where ancient traditions meet cutting-edge technology. Sloan’s signature worldbuilding—full of hidden societies and quirky detail—makes the city come alive with possibility.

If the constant surprises and secret societies of Penumbra’s kept you turning pages, prepare for The Library at Mount Char. Carolyn and her fellow 'librarians' guard a collection of knowledge far more bizarre than any Google search. Every chapter unspools a new, jaw-dropping twist, challenging your expectations and keeping you guessing until the very end.