Divergent author working on new series

Veronica Roth fans can start the countdown.

The Divergent author is set to write a new two-book series, HarperCollins Children's Books told The Associated Press on Monday. The books currently are untitled, with the first one expected in 2017 and the next in 2018.

Roth and her publisher offered few specifics, beyond saying the series is in "the vein of Star Wars" and will tell of a boy's "unlikely alliance" with an enemy.

"Both desperate to escape their oppressive lives, they help each other attain what they most desire: for one, redemption, and the other, revenge," the publisher announced.

In a recent email to AP, Roth wrote that "The idea started with a character. All the other elements - setting, world, even a substantial portion of the plot - came after." She added that while she had a "pretty detailed" outline for the new series, she was still in the early stages of writing.

"That's why I'm being so vague," she explained.

Divergent, a Dystopian trilogy Roth completed in 2013, has sold more than 30 million copies and along with Suzanne Collins' The Hunger Games and John Green's books helped perpetuate the strong growth of young adult novels. The first Divergent movie, starring Shailene Woodley as teen heroine Tris Prior, came out a year ago and quickly earned more than $US100 million ($A127.86 million) at the box office. Three more movies are planned, starting with the March 20 release of Insurgent.