I know a few collaborative writing teams who publish under a joint pseudonym (Daniel Abraham and Ty Franck, for example, who publish the Expanse novels under the name James S. A. Corey), and I even know a few husband and wife writing teams (like Ann & Andres Aguirre, who write urban fantasy under the name A. A. Aguirre, and bestselling fantasy authors Ilona and Andrew Gordon, who write under the name Ilona Andrews). But I’d never heard of a pair of siblings writing under one name — or at least I hadn’t, until I came across Sherylyn and Karen Dunstall, who write together under the name “S.K. Dunstall.”

Their first book was Linesman, published in paperback by Ace in June of last year. My friend Sharon Shinn called it “Full of fast action, interplanetary intrigue, appealing characters, and a fascinating new take on the idea of the sentient spaceship.” My son Tim, who’s currently studying physics in college, read it in virtually one sitting, and loved it — so much so that when I gave him an advance proof of the second volume, Alliance, for Christmas last year, he happily disappeared for hours.

The third volume in what’s now being called the Linesman series, Confluence, arrives in paperback from Ace at the end of this month. Great timing! That’s my Christmas shopping for Tim done.

Here’s the publisher’s description of the first volume:

First in a brand new thought-provoking science fiction series.

The lines. No ship can traverse the void without them. Only linesmen can work with them. But only Ean Lambert hears their song. And everyone thinks he’s crazy…

Most slum kids never go far, certainly not becoming a level-ten linesman like Ean. Even if he’s part of a small, and unethical, cartel, and the other linesmen disdain his self-taught methods, he’s certified and working.

Then a mysterious alien ship is discovered at the edges of the galaxy. Each of the major galactic powers is desperate to be the first to uncover the ship’s secrets, but all they’ve learned is that it has the familiar lines of energy — and a defense system that, once triggered, annihilates everything in a 200 kilometer radius.

The vessel threatens any linesman who dares to approach it, except Ean. His unique talents may be the key to understanding this alarming new force—and reconfiguring the relationship between humans and the ships that serve them, forever.

And the back-cover text for Alliance:

As the Linesman series continues, linesman Ean Lambert finds himself facing an alien ship he doesn’t understand — and a terrifying political threat he cannot fight…

The lines. The soul of every ship. It was once thought there were only ten, but that was before an alien vessel appeared at the edge of space — before Ean Lambert heard more lines singing. Ean’s ways of communicating with lines is strange. But his abilities make him a valuable tool — or weapon — to command.

Captain Selma Kari Wang has lost everything — her ship, her crew, her legs. But the New Alliance of Worlds is not done with her yet. After they rebuild her broken body, they send her to captain one of the new alien ships, teaming her up with Ean, the only one who can understand the alien lines.

Kari Wang and Ean are poised on the threshold of discoveries that could change the world. But not everyone wants the New Alliance to control the secrets they uncover—and those who oppose won’t hesitate to do whatever it takes to stop them…

And finally for Confluence:

From the national bestselling author of Alliance, linesman Ean Lambert finds himself caught in a dangerous fight for political power…

The lines. Mysterious yet familiar: the key to controlling every ship in the galaxy. Once they were thought of as tools, but since linesman Ean Lambert discovered strange new lines in an alien vessel, they have become so much more — symbols of a power too great to ignore.

While the Crown Princess of Lancia seeks to share the new technology, her father, the Emperor, has other plans. His latest political maneuverings seem to be tilting the balance of control to Lancia’s favor — a move that not all members of the New Alliance are looking upon favorably.

As tensions mount, Ean and his former shipmates must unite to avert a disastrous conflict: the princess working within the tumultuous Alliance, Ean seeking the help of the impatient alien ships, and Ean’s close friend and bodyguard, Radko, embarking on a mysterious and perilous mission.

But the biggest threat comes from an unexpected source. Someone is trying to take down the New Alliance from within — and will use anything, even the lines themselves, to ensure its destruction…

And here’s the complete publishing details:

Linesman (384 pages, June 30, 2015)
Alliance (400 pages, February 23, 2016)
Confluence (400 pages, November 29, 2016)

All three book are published by Ace, priced at $7.99 for both print and digital editions. The covers are by Bruce Jensen. Visit the authors’ website here.

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