BTS, not Taylor Swift, are authors of mystery 544-page book coming out in July

Pre-sales of the memoir have already soared in US charts

BTS are currently on hiatus as members complete their mandatory military service in South Korea. AP Photo

The author behind a mystery book set to be released this summer has now been revealed.

The book, known only as 4C Untitled Flatiron Nonfiction Summer 2023, began to soar up the US sales charts after many Taylor Swift fans believed the singer had penned a surprise memoir. Very little information was provided about the book but fans came to this conclusion after apparently putting together clues.

However, it is now been revealed the memoir — which was supposed to unveil its author on June 13 — isn’t Taylor Swift, but rather an equally popular music group with a massive fanbase: the K-pop group BTS.

Beyond the Story: 10-Year Record of BTS is written by journalist Myeongseok Kang along with the members RM, Jin, Suga, J-Hope, Jimin, V and Jungkook and will be put together as an oral history of their story as a band. It has been translated into English by Anton Hur, in collaboration with Clare Richards and Slin Jung.

The book is available to pre-order for $45 (Dh165) and has been hovering in the top 10 of the Amazon book sales and is at number one in the Barnes & Nobles pre-order charts.

Interest in the book began when US booksellers shared news that an untitled work with an initial print run of one million copies was coming on July 9. The huge number and short time between its announcement and arrival date suggested it would be a famous author.

Publisher Flatiron Books also issued a release saying would have “global appeal” and “massive publicity” while describing it as a “biography or autobiography” that would feature 40 colour photos.

The early details about the untitled work were picked up as clues by both fans of Swift and BTS, such as the original author reveal date of June 13 with 13 being Swift’s favourite number but also the date of the 10th anniversary of the K-pop band’s first single, No More Dream.

Another clue involved the 544 page count with the numbers 5, 4 and 4 adding up to 13. Even the release date of July 9 raised eyebrows for BTS fans. It is Army Day, which celebrates the day the name "Army" was first coined for the band's fanbase. However, it is also two days after Swift releases her re-recorded album Speak Now (Taylor’s Version).

In October, BTS's record label confirmed the members would begin their mandatory military service and would reunite in 2025 when all had completed it. The oldest member of the band, Jin, began his military service in December, with J-Hope following in April.