Robert and Sheryl Adamson who were found dead in their Murrumbeena home. Pictured with their son Michael. Hemming did not know the Adamsons, who had two children, Michael, 28, and Katie, 30, but had seen them in the local area walking their dogs when he decided to act out his fantasy to find out what it was like to kill someone. He walked about 160 metres from his home to the Adamsons' house in Omama Road at about 6am, knocked on the couple's front door and asked to use their phone. The Adamsons, who were both wearing pyjamas, invited Hemming inside in the spirit of being good neighbours. Hemming, armed with a Cold Steel Marauder knife he had ordered online, followed the couple down the hallway before attacking Mr Adamson, an accountant, in the living room area, stabbing him repeatedly. Mrs Adamson, a librarian at Melbourne Grammar School, hit Hemming over the head with a broom trying to save her husband of 33 years.

Hemming then stabbed Mrs Adamson in the neck, chest and back before walking home and hiding his bloodied clothes under his bed. The knife was found embedded in Mrs Adamson's upper right shoulder and neck area. After his arrest, Hemming told police he felt that morally it was better to kill an old couple than someone young, that he had found himself thinking of killing people over the past few months, and that on the night of the murders he was drunk and impulsive and didn't have the common sense not to go through with his fantasy. "I just kind of find myself thinking about killing people," Hemming told police. "Just don't even realise ... in no specific ways." Justice King described the autopsy reports on the Adamsons as "chilling" as they showed "a degree of ferocity in the blows inflicted, in that they were deep and penetrating, as well as numerous".

The judge said Hemming, a former De La Salle college student who has the autism spectrum disorder Asperger Syndrome, had exceedingly poor prospects of rehabilitation. "You know what you did was wrong but there is nothing to indicate that you would not do it again as you lack an emotional connectedness with people in general," Justice King said when jailing Hemming for 32 years with a non-parole period of 27 years. Psychiatrist Dr Daniel Sullivan did not believe Hemming was a psychopath or sociopath but that he had a lack of empathy and the risk of him re-offending was "unknowable". The judge said Hemming's Asperger's, which was not normally a syndrome that caused people to be violent, did not reduce his moral culpability. Hemming remained incapable of feeling genuine empathy, sorrow or regret for his fellow human being.