Perry Kouroumblis will be brought into Melbourne Magistrates Court on Wednesday morning, after being charged over the 1977 deaths of Suzanne Armstrong, 28, and Susan Bartlett, 27.
The 66-year-old, who is in custody, is due to face the first day of a committal hearing where evidence will be tested before a magistrate decides whether to commit him to trial in a higher court.
Several witnesses are expected to be called and cross-examined at the committal, which may span three days.
Kouroumblis, a dual Greek-Australian national, was arrested on an INTERPOL red notice after travelling to Italy in September 2024, and then extradited to Australia in December.
He had been living in Greece since 2016, but was unable to be arrested due to a 20-year statute of limitation on the initiation of murder charges.
Ms Armstrong and Ms Bartlett were found dead with more than two dozen stab wounds at their Easey Street property in Collingwood, while Ms Armstrong's 16-month-old son Gregory was left unharmed in his cot.
Kouroumblis has been charged with the pair's murder, between January 10 and January 13, 1977, and with one count of having "carnal knowledge" with Ms Armstrong without her consent.
He is yet to enter a plea on each of the three charges.
The accused murderer will be represented by top silk Dermot Dann KC, who told the court last week he had only recently been briefed on the case.
Kouroumblis faced court this week via video link from prison, where his junior barrister Daniel Sala asked for disclosure of evidence from Australian Federal Police and Victoria Police, which prosecutors are seeking to keep confidential.
This included "material disclosed to INTERPOL by Victoria Police" and evidence on how a forensic sample was taken from Kouroumblis, Mr Sala told Melbourne Magistrates Court on Monday.
The committal hearing will begin at 10am on Wednesday.
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