WILLIAM and Edith Moffat were in their dressing gowns and slippers when they answered a fateful knock at the door of their home in the early hours of the morning on September 22, 1977.
It is not known who was standing at their door that night, or why, but what happened next would shock Maryborough to its core and puzzle detectives for years to come.
The middle-aged couple were led back to their bedroom in their Jupiter St home where pillows were placed on the floor and nylon cord was used to tie their hands behind their backs.
It is believed Mr Moffat was forced to tie the cord around his wife's hands as detectives later found a similar knot on a temporary clothesline outside the home.
Two bullets were fired and both husband and wife died instantly at the foot of their bed in an execution-style killing.
The Moffats' deaths remain one of the state's greatest unsolved crimes, with the Queensland Police Service offering a $250,000 reward to anyone with information that helps solve the mystery.
The motive behind the murder of couple continues to baffle investigators to this day.
In the weeks following their deaths, hundreds of people were interviewed and most of Maryborough's .22 firearms were seized and tested.
Maryborough police Sergeant Bruce Hodgins said detectives had received pieces of information over the years, but none led to the killer.
He said the gunshots were heard about 3am by a neighbour across the road.
Sgt Hodgins said it was among the most shocking crimes in Maryborough's history.
The couple were discovered later in the day by friends who became concerned after Mr Moffat didn't go in to work.
"It must have been horrendous for these people to find the bodies in that situation," Sgt Hodgins said.
Now, after four decades without answers, the police are reopening the case and asking anyone who knows what happened that night to come forward and finally see justice served for the couple, who had been married 27 years.
Sgt Hodgins said finding the person behind the murders would give closure to Maryborough community.
He said anyone with information that may have previously been afraid of sharing what they knew was encouraged to do so now.
"We need them to stand up and come forward if they know something," Sgt Hodgins said.
The double murder of the well-known and humble couple sent shock waves through the community.
Mr Moffat, 51, was a bank manager, property valuer, Scout enthusiast, church secretary and member of Lions.
He had been a close friend of then-premier Sir Joh Bjelke-Petersen while working as a bank manager in Biggenden and Kingaroy, handling the politician's bank account.
Mrs Moffat, 50, worked with many of the Heritage City's community groups.
The night before their slaying, Mr Moffat went to a United Church meeting and Mrs Moffat went to a fashion parade.
There were few clues after the murder of the childless couple - two bullets fired from a .22 calibre revolver or rifle, two lengths of thin pink cord and a white Valiant AP5 seen outside the Moffat's home about 5.30am on the day of the murders.
The two bullets found embedded in their skulls were from different manufacturers, but police believed there was only one shooter.
It is believed a professional hitman may have been behind the killings.
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