Victorian woman Marea Yann was found dead sitting in an armchair in her home almost 20 years ago.
Now Victoria Police are offering a $1 million reward for information that leads to the conviction of the person or persons who killed her.
Mrs Yann, 69, was found on the morning of September 30, 2003, by a gardener working at her home in Healesville, in the Yarra Ranges, northeast of Melbourne.
"Marea was sitting in an armchair in her loungeroom and had suffered extensive head and upper body injuries from an assault," police said in a statement on Tuesday.
"She was wearing a red jumper, black pants and slip-on shoes, and had not yet dressed for bed."
The TV was still on but there was no sign of a forced entry and her purse, seemingly untouched, was on the floor.
Police later determined she had probably been killed on the night of September 29.
In February 2006 a then 46-year-old man, who was known to Mrs Yann, was charged with murder but he was acquitted after the case went to trial two years later.
The case was reopened in 2021.
This is the second reward to be put up to solve the case. The first was $100,000 offered in October 2005.