There are 4 books in the Jim Henson's the Dark Crystal series.
The Jim Henson's the Dark Crystal series does not have a new book coming out soon. The latest book, Flames of the Dark Crystal (Book 4), was published in September 2019.
The first book in the Jim Henson's the Dark Crystal series, Shadows of the Dark Crystal, was published in July 2016.
The Jim Henson's the Dark Crystal series primarily falls into the Fantasy genre. This young adult series was written for ages 12-17, but can be enjoyed by adults too.