Niland's secret passion for many years has been ancient history, Roman archaeology and most particularly the tale of King Arthur and the magician, Merlin.

There is no literature associated with the legend that she has not picked apart, nor an Iron Age fort in Britain she has not climbed. She visits south-east England most years, dragging along her obliging husband, the former university vice chancellor John Niland.

"When one is active in public life, particularly in some of the difficult jobs I have had there has to be peace somewhere in your life," says Niland. "And for me that was meditation, reading but particularly pursuing the Arthurian legend and the Merlin legend."

All that zeal has been lately channelled into the publication of her first fiction title. A Darker Magic This Way Comes is book one in a young-adult series that sees a teenage Merlin travelling 1500 years in time to meet a thoroughly modern girl – the daughter of an archaeologist digging the ruins of Okehampton Castle in Dartmoor.

Niland's version of Merlin is most unlike the white-bearded, pointy-hatted wizard of popular cinematic culture. Her Merlin is handsome and tall, with a Roman nose and black shoulder-length hair. He is a child prodigy and polymath, also trained in shape-shifting, complex enchantments and combat with the Darker Arts.

"He's a hot, young wizard", Niland says. "Merlin is good looking, he's got terrific musculature and he is of this world. My first job was as a teacher teaching gifted children and they were thoroughly into Merlin because they saw in him something like themselves.

"They were able to draw, they were quite good at sport, they were able to act, they could read poetry, they could write poetry; they were attracted to a person who could do this as well. But my Merlin is like Leonardo da Vinci with a wand."

Niland places Arthur in the late fifth century leading the defence of lands against Saxon invaders and embraces the legend of Sir Galahad, son of Lancelot, and the hunt for the Holy Grail.

Merlin's reputation for "magic" was probably a combination of sleight-of-hand magic, says Niland, and the tricks of science as taught by the Druids – magnesium flaring on the palm could appear to the untaught mind like conjuring lightning.

"But I also believe it was something else, I also believe that Merlin could tap into some ancient wisdom that we have long lost contact with. My Merlin flies and goes between the realms."

Her interest in the Arthurian legend was kindled by a childhood reading of Terry Hanbury White's The Once and Future King. The idea for a book began coalescing 10 years ago in the aftermath of the "scarifying experience" as director general of the then NSW Department of Community Services.

Niland's tenure was controversial. No one doubted her genuine motives but she came to the portfolio at a time of crisis and critics like Alan Jones doubted her abilities to manage the department's response to a rising tide of child abuse claims. She departed with the minister in 2002.

"To explain to people what that [time] was like, I've never been able to do because it is too painful," Niland says. "But for people who see now the Royal Commission night after night, they get a hint of what it was like to deal with stories like that on a daily basis, deal with the people behind them, to deal with legislation that made it  criminal for you to even talk about their side of the story, whether it was right or wrong."

Approaching the story of Merlin and Arthur as a puzzle, Niland voraciously read crime novels in preparation for novel writing, which she did in "the corners of her day" over five years.

It took another five years to find a publisher. "I would present as a woman of mature years and say, 'This is the book, I've got four more', and they'd say, 'Here's yet another one who thinks they are J.K. Rowling'."

Niland has mapped out a further four books, taking Merlin from birth to his death at age 120. Eventually she signed up with her literary agent's new on-demand publishing venture, Shimran.

"My book is definitely for those who are too young to read Game of Thrones and yet too old for Harry Potter."

A Darker Magic This Way Comes

Carmel Niland

Shimran, $30

Linda Morris is on Facebook and Twitter @LindaMorrissmh