Two of the biggest books of 2025 were technically published in December 2024—Mel Robbins’ The Let Them Theory (Hay House, 12/24/24) and Callie Hart’s Quicksilver (Forever, 12/3/24). They didn’t make our list of the biggest new books last year, but continued going strong enough this year to deserve mention here. In fact, The Let Them Theory was the top-selling print title of 2025 with 2.8 million units sold. Quicksilver came in at 34 in Circana Bookscan’s top 200. Suzanne Collins’ addition to the Hunger Games universe was the top newly-published 2025 book of the year, selling more than 2 million […]
