Olivia Hope's father has some questions for the man jailed for her killing, after reading a new book about the case.
Watson is serving 19 years for killing the 17-year-old and Ben Smart after a 1997 New Year's Eve party in the Marlborough Sounds.
Elementary-- The Explosive File on ScottWatson and the Disappearance of Ben and Olivia, written by journalist Ian Wishart, is due out tomorrow and purports to have found the mystery ketch in the case.
Listen: Gerald Hope speaks to Newstalk ZB's Chris Lynch about the new report
He said Mr Wishart's book opened his eyes to some of the evidence that wasn't used in the trial.
The Herald revealed today a report by the Maritime Research Group which includes a photo of a blonde woman on the back of a runabout on January 5, 1998, which the authors say is Olivia Hope.
The group's report paints the ketch as having a central role in the smuggling of cocaine.
The suggestion of a drug syndicate's involvement in the murders was "chilling", Mr Hope said.
"It scares the sh*t out of me. This stuff obviously goes on but it's a sector most normal New Zealanders have nothing to do with; let alone understand how it operates.
"The scale of what they're proposing there; the quantities of cocaine being imported [is] chilling."
Mr Hope believed there were two questions in particular which still hadn't been answered.
Watson might be able to fill some gaps, he said.
"Scott Watson is key to all this. He's been in jail for 19 years; there's questions I have to ask him and hopefully I'll have the opportunity to.
Scott Watson. Photo: John Kirk-Anderson / FairfaxNZ
"At the end of the day, all we want to do as a family is demystify the disappearance of Olivia and Ben."
That resolve would come when it was clear in everyone's mind what happened on January 1, 1998, he said.
Finding Olivia and Ben's remains was also important to the family.
"[Olivia's] dreams and expectations were never realised, nor were Ben's.
"A quarter of our family had its heart ripped out. That ripple effect has been with us for the past 19 years. It does damage people and it changes your view of society and changes your view of relationships.
"My belief is there's people out there that definitely have information that could assist us."