Rebecca Yarros’ ‘Untitled Empyrean’ Book Is Up for Preorder

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Rebecca Yarros’ next book doesn’t have a title yet, but it’s already a bestseller online. The book, currently known as “Untitled Empyrean,” also doesn’t have a cover. But it does have a release date. The novel comes out on Sept. 29, which was enough information to push it to No. 1 on Amazon’s best-selling book charts, and it charted on other online booksellers like Bookshop.org.

The immediate success of the as-yet-untitled book even took Yarros by surprise, who wrote on Instagram, “Okay, so I had this little idea about a year ago to drop a surprise for you guys. But then you not only found it as soon as my publisher put it on preorder, but shot it straight to number one on Amazon without a cover, title, or even a vague idea of what might be coming your way!?!? You’ve rendered me speechless.”

As the online listing states, the upcoming book by the fantasy-romance novelist is related to the best-selling Empyrean series, but it is not book four. Yarros clarified on social media that the upcoming untitled book “hasn’t altered book 4’s timeline in the least,” and added that it is also not the graphic novel adaptation of the series.

Yarros has written well over a dozen novels, but the Booktok favorite is best known for the Empyrean series, which started with 2023’s Fourth Wing. That same year, it was announced that the first novel would be adapted into an Amazon Prime series.

The series is currently in development from Michael B. Jordan’s Outlier Society, who told Deadline in February, “We are making sure that this is going to be an exciting show that delivers on all of the things the fans want and some of the things that they won’t be expecting either.” Meredith Averill was tapped as showrunner, but there’s still no release date or news about the cast.