Imagine if someone was to dump you by declaring that your whole relationship never happened — it was just a legend. Then, years later, they want you back, but you suspect it might be just because they want to hang out with a mutual friend they haven’t seen much since the breakup.

Well, Timothy Zahn took the Star Wars franchise back, and he brought his blue-skinned friend Mitth’raw’nuruodo with him. The Chiss, known as simply “Thrawn” to most of his friends and enemies, was the star villain of Zahn’s blockbuster Thrawn trilogy (1991 to 1993), the books that helped pave the way for the prequels and all that came after: they showed George Lucas just how much demand remained for new Star Wars stories.

Those books, and two more Thrawn novels by Zahn, were cleared from canon when Disney swept the decks after acquiring Lucasfilm in 2012. Five years later, after making a canon cameo in the Star Wars: Rebels TV series, Thrawn came back in a big way with Thrawn, the first book of a new trilogy by Zahn. The series continued with last year’s Thrawn: Alliances, and now Thrawn: Treason brings it to a close.

With the continuity reboot, Zahn got a whole new playground for his tactical mastermind to study. Plus, whereas the original Thrawn trilogy took place after the fall of the Empire, the new books are set in the years leading up to the debut of the Death Star. (That’s also the era of Rebels, people and places from which are referenced in the latest novel.)

That means that Thrawn gets to brush shoulders with Imperial heavies who were long gone by the time he showed up in Heir to the Empire. Alliances was practically a Darth Vader buddy comedy, and Treason finds the grand admiral drawn into the power struggle between Grand Moff Tarkin and Director Krennic.

It’s the latter’s pet project, “Stardust” (that’s no moon), that needs Thrawn’s help in Treason. One of the battle station’s supply lines is under siege by a flock of creatures described as bigger, badder cousins of the power-sucking mynocks Han and Chewie had to shoot off the Millennium Falcon in The Empire Strikes Back. Thrawn is promised funding for one of his pet projects if he figures out how to get the creatures out of the way within a week.

That sounds like the setup for a darker, longer version of The Trouble with Tribbles, but Thrawn correctly guesses there’s more going on than just an interstellar infestation. He follows a trail that leads to a ship from his native Chiss Ascendancy, the question of his potentially divided loyalties elided by the fact that the Chiss and the Empire share a common enemy in the form of a calculatingly aggressive species called the Grysk.

The entire new trilogy gives readers an extensive backstage view of the Galactic Empire during the rise of the Rebellion. One of Zahn’s niftiest tricks is getting readers to root for an Imperial officer, which he pulls off by making Thrawn markedly different from cold-hearted officers like Tarkin and Krennic. Thrawn’s demeanor is icy, but he’s an empathetic leader who refuses to waste lives wantonly. The Emperor barely trusts him, but Thrawn is such an effective commander that Palpatine can never justify canning or even demoting him.

Thrawn’s signal skill is reading his opponents and anticipating their actions, and Treason builds to a dazzling showcase in which the grand admiral essentially fights two major space battles at once with his hands tied. Eli Vanto, Thrawn’s faithful translator-turned-collaborator from the trilogy’s first novel, is back; as we learn more about where he went and why, we gain a fuller sense of the web Thrawn is weaving between the Empire and the Ascendancy.

Also back: Marc Thompson, marquee narrator of Star Wars audiobooks. In addition to his dead-ringer voices for the Emperor, Tarkin, and Krennic (who spends much of Treason trying and failing to suppress his rage), as well as his deliberately understated Thrawn, Thompson has fun with supporting characters including a buffoonish Krennic assistant and a pair of quietly thuggish Death Troopers. He even channels Chekov for a member of Thrawn’s bridge crew.

Yet another returnee is John Williams, whose iconic themes were absent from the most recent Star Wars audiobook, Alphabet Squadron. Although that production’s generic score was nothing to write Coruscant about, it was refreshing to have a Star Wars story where cues written for very specific movie scenes weren’t mashed into places they obviously didn’t belong, it’s nonetheless nice to have the classic music back — along with a fuller complement of sound effects compared to the relatively bare-bones Alphabet Squadron.

One of the Random House Audio producers’ subtle touches in Treason is to recruit the kind of bright, optimistic cues associated with the Rebellion in the movies and deploy them in situations where Thrawn and his allies are triumphant. Listening to the story, you can almost forget that the eponymous officer is serving a government that’s about to obliterate an entire planet full of people just because it can.

In these three entertaining war stories, Zahn keeps us engaged with a character who can consistently penetrate the plans and motivations of just about everyone he encounters — while Thrawn’s own motivations remain elusive. Who committed the titular treason, and how? Even by the end of the book, the answer may not be as clear as you’d think.

– Jay Gabler