On 22 March 1975, Noel Milton Weckert and his wife Sophia Janine Weckert were travelling along the Bruce Highway between Rockhampton and Mackay, Queensland, en route to a skydiving event at Emu Park. The couple had departed Townsville the previous afternoon and apparently stopped near the Connors River, between Sarina and Marlborough, for a break. Noel Weckert was shot twice at close range while seated in his stationary, seat-belted vehicle, sometime between 4 am and 4:30 am. His body was discovered by a truck driver at around 6 am.
Sophia Weckert was missing from the scene, and police believed she had been abducted by her husband's killer. A large search operation followed, including roadblocks along the highway between Townsville and Maryborough, an investigation into a sighting of a similar vehicle near the Queensland/New South Wales border at Wallangarra, and the apprehension of a man and woman stealing fuel in Brunswick Heads. Police divers searched waterholes along the Connors River. On 27 March 1975, a local man with car trouble discovered Sophia Weckert's body near Kennedy Creek, roughly 30 kilometres north of where her husband had been found. Police believed she had been shot in the back while trying to flee.
Initial investigative focus centred on a prison escapee from Palen Creek Correctional Centre, who was arrested in a raid at Wavell Heights on 30 March 1975 but was cleared of involvement after police concluded he had been in Brisbane at the time of the murders. The Queensland Government offered a $20,000 reward on 1 April 1975. In June 1975, police obtained admissions from two inmates at Goulburn Jail in New South Wales, leading to the extradition of Raymond John Wylie and Maxwell John Harper, and separately of Janice Christine Anne Payne, a 17-year-old from George Town, Tasmania. All three were charged with murder and appeared at Mackay Magistrates Court on 9 July 1975, later being committed to stand trial following proceedings in Mackay.
Two trials were held in Rockhampton. In the first, concluding in early 1976, Wylie was found guilty of murdering Noel Weckert and sentenced to life imprisonment; Harper and Payne were convicted of manslaughter and sentenced to seven years. In the second trial, concluding 23 February 1977, Wylie and Harper were found guilty of murdering Sophia Weckert and sentenced to life imprisonment, while Payne was convicted of manslaughter and sentenced to ten years, partly concurrent with her earlier sentence. Appeals by Harper and Payne were dismissed by the Queensland Court of Criminal Appeal in May 1977, and Payne's further application to the Full High Court was refused in November 1978.
The murders intensified public concern about safety on the Bruce Highway between Marlborough and Sarina, an area already known as "death alley" and later "The Badlands" due to repeated violent incidents. Police increased highway patrols in response, and the road was realigned in 1982.