"I was writing an English assignment on the disappearance of Mona Blades," says Scott.
"I actually went to Rotorua and interviewed one of the investigators as part of my research."
It was later as an adult, married and with children, that he returned to writing — concentrating on well known missing cases from recent history.
"I love history and I love a mystery," he says.
The success of both the first books led to two series of the television series Missing, with Scott presenting.
He says they had some successes, but there were still a lot of questions.
Scott then turned his attention to unsolved New Zealand murders between 1920-30 in Shot in the Dark.
That fuelled his passion for crime-solving, and in his next two books — The Bassett Road Machine-Gun Murders and The Great New Zealand Robbery he applied more in-depth analysis to one famous incident in each volume.
Scott says he wants to continue in that vein, because it is interesting and exciting — but he was also drawn back to his earlier works by the public.
"Whenever I spoke, it was the stories about missing people that the public wanted to know about," he says.
"I had another read of my earlier works and found some lacked substance and some we knew more about now because more information came to light," Scott says.
The Missing Files — Unsolved New Zealand missing cases looks at a number of the earlier cases through fresh eyes and with that new information, plus visits six new cases.
Scott says it was also timely to continue the earlier work, because investigators and police who worked on the cases originally aren't getting any younger.
He says working and writing is his life.
Holidays are spent travelling only where he can do research or interviews, and he is fortunate his wife and children understand that.
He enjoys the diligence it requires and the commitment to meet deadlines.
But most of all Scott likes history and a good mystery — and you certainly can't beat the real thing.