A one million dollar reward has been posted as part of a police investigation into the mysterious death a 41-year-old mother in Melbourne 46 years ago.

Press PLAY to hear the full mysterious case from police

Mary Anne Fagan died under suspicious circumstances in her Armadale home on Dandenong Road on Friday, Febaruary 17 1978.

Police are hopeful this new reward will encourage someone to come forward with information.

Anyone with information is urged to contact Crime Stoppers on 1800 333 000.

Images: Victoria Police