Half a century after the bodies of two men were found near a cattle station in one of the most remote parts of the Northern Territory, Glen Chatto knew finding answers was always going to be a "long shot".
When police first found the two men's remains near Mount Bundy Station, 110 kilometres south of Darwin, in 1976, while they were intrigued by the circumstances, they had little to go on.
Investigators believed the pair likely ventured out to the remote place together, but by the time the bodies were discovered, they'd already been in the elements for years.
In the decades since, forensic science has advanced in quantum leaps, so by the time the file landed on Acting Sergeant Chatto's desk, he was able to enlist the help of experts in the field at the Australian Federal Police.
Using the same technology Californian detectives deployed in the effort to identify Golden State serial killer Joseph James DeAngelo Jr, the AFP scientists went to work.
While Acting Sergeant Chatto says "FIGG gives us a very good idea" when an investigation is on the right track, it wasn't enough on its own "to build a case to take to the coroner for an identification just yet".
By going back through Trevor's "fairly chequered past", Acting Sergeant Chatto found a clue in old arrest records that yielded the next piece of the puzzle.
Kathy's brother managed to clean up his act too and the last time she remembers seeing Trevor was about 1970, two years before his last confirmed proof of life.