LOS ANGELES - Veronica Roth, author of the best-selling Divergent book trilogy, reveals she started out with a male protagonist, but the story did not gel until she changed him into a teenage girl named Tris.
The author consciously styled Tris as a symbol of female empowerment, a complex character who has a hand in her own destiny.
Roth - who at 25 is just a few years older than Shailene Woodley, 22, the actress who plays Tris in the movie adaptation of her Divergent novels - has not looked back since.
The novel Divergent - her first book which she penned while still an undergraduate at Northwestern University - was published in 2011 and became a New York Times bestseller, winning her Best Author honours from the reader website Goodreads.
Comparisons to The Hunger Games books by Suzanne Collins, which also features a young female heroine as a freedom fighter in a repressive society, did not seem to hurt.
Instead of Collins' "districts", the world of Divergent features a society ruthlessly segregated into five sections by supposed personality type, with any individual who does not fit neatly into one of these categories ostracised.
Roth wrote two more instalments in 2012 and last year, Insurgent and Allegiant, and the movie rights to the series were quickly snapped up.
Speaking to Life! during the press tour for the film, which opens in Singapore on Thursday, she says she is pleased with director Neil Burger's interpretation of her story, which she says "matches up pretty well" with the world she pictured in her head.
And although loyal fans of the book might be nervous about alterations in the movie version, she says she is happy with the way it was adapted, even though this meant making some changes and condensing certain aspects of the tale.
"Some things don't translate visually. The entire book is written in Tris' head and so there has to be ways of showing what she's thinking and going through on the screen, and that, I think, requires some changes. And so I was pretty open-minded to it, it wasn't that difficult for me.
"So for me, it's been a very positive experience."
Roth admits, unusually, that she reads a lot "in my genre because I think it's important to know what your peers are doing".
"So I read a lot of young adult fiction,'' she says, adding that the success of The Hunger Games and other titles in the genre paved the way for her own, with many of their readers migrating to Divergent when it came out.
"My favourites of all time - I was a big Harry Potter geek, but I also loved The Giver by Lois Lowry."
On the prospect of the inevitable comparisons of her work with that of Collins' and other young adult writers, she says: "There's so much going on in young adult fiction and, as they say, there's nothing new under the sun.
"I didn't try intentionally to be different. I just tried to tell a story that felt interesting to me and honest.