There are 4 books in the Star and the Shamrock series.
The Star and the Shamrock series does not have a new book coming out soon. The latest book, The World Starts Anew (Book 4), was published in December 2020.
The first book in the Star and the Shamrock series, The Star and the Shamrock, was published in May 2019.
The Star and the Shamrock series primarily falls into the Historical genre.