Top positive review
Third in the Star Wars trilogy which began with "Thrawn" and continued with "Alliances"
Reviewed in the United Kingdom on 17 January 2020
Any book by Timothy Zahn will almost certainly be worth reading, and the central figure of this one - Grand Admiral Thrawn - is both one of the most interesting characters Zahn has ever created and one of the best in the "Star Wars" universe.
The books in which the character originally appeared, starting with "Heir to the Empire" in 1991, were subsequently declared "non canon" by Disney, but the character of Thrawn was too good to ignore so he was re-introduced to the canon in series three and four of "Star Wars: Rebels."
"Thrawn: Treason" is the third novel in a new trilogy by Timothy Zahn, mostly set rather earlier than the original books and carefully brought into line with the most recent films and canon. That trilogy consists of:
1) "Thrawn" (2017,) which describes how he joins the empire and rises to the rank of Grand Admiral,
2) "Thrawn: Alliances" (2018,) a novel with two parallel storylines many years apart, the first featuring a collaboration between a younger Thrawn and Anakin Skywalker, the latter one between Grand Admiral Thrawn and Darth Vader
3) "Thrawn: Treason" (2019) set shortly before "Rogue One" and "The Empire Strikes Back" in which Thrawn, Vader, Grand Moff Tarkin, Director Krennic and various other characters face both internal and external threats to the Empire and the Galaxy - and not until the very end does it become clear who is really contemplating or committing treason.
"Thrawn" is the core name (which humans can pronounce) of a Chiss military genius whose full name is Mitth'raw'nuruodo. The Chiss race are tall, solidly built humanoids who appear almost completely human except for their blue skin and red eyes.
Their political unit, the "Chiss Ascendancy," in whose military forces Thrawn originally served, is not part of the Empire, and the biggest mystery about him is why in the galaxy he would want to serve Emperor Palpatine. Thrawn has a very different style to most Imperial commanders - he is far cleverer than any of them, leads by inspiring loyalty and rewarding good service rather than through fear, and entirely lacks the megalomania and xenophobia of Palpatine and most of his minions.
Timothy Zahn has dropped a number of hints in this trilogy which suggest why Thrawn might believe that the interests of the galaxy, including his own species, might be served by strengthening Palpatine's Empire, and in this book the idea which Zahn has been hinting at appears to be confirmed.
"Thrawn: Treason" is a well-written, entertaining and fast paced book, with a complex plot, but not too complex for most SF readers to follow. It will probably give most pleasure to readers who have at least a passing familiarity with the Star Wars universe - though you certainly don't have to be a Star Wars fanatic to enjoy it - and is also best read in sequence with the rest of the trilogy, e.g. start with "Thrawn" and then read "Thrawn: Alliances" and finish with this book.