Rebecca Yarros, the author behind the popular fantasy romance series Fourth Wing, has announced the title and release date for a new book in The Empyrean series. Titled Threshing Day, the book is scheduled to launch on September 29, 2026.
Yarros initially teased the upcoming book, then referred to as "Untitled Empyrean," in April, allowing preorders which quickly propelled it to the number two spot on Amazon's charts despite the lack of a title. The official reveal coincided with Conscription Day, July 15, a significant event within the series where cadets face a perilous challenge to become dragon riders.
In an Instagram post, Yarros detailed that Threshing Day will feature a collection of 13 stories, each focusing on fan-favorite characters during their own Threshing Day—the pivotal moment they bond with their dragons. The deluxe edition will include 16 full-color original art pieces by artist Joe Requeza.
Significantly, the book will include a story from Xaden's perspective, a long-requested point-of-view from readers. Yarros also confirmed that she is actively working on the fourth main installment of The Empyrean series, though no release date has been announced. The series began with Fourth Wing on May 2, 2023, followed by Iron Flame on November 7, 2023, and Onyx Storm on January 21, 2025.
The immense popularity of The Empyrean series has also spurred a television adaptation in development at Amazon MGM Studios and Michael B. Jordan’s Outlier Society. It remains to be seen if any narrative elements from Threshing Day will be incorporated into the show.
Threshing Day is currently available for preorder and will be released on September 29, 2026.