Boroondara Crime Investigation Unit detectives are investigating a theft from a jewellery store in Camberwell this month, Victoria Police say.
It is believed a male parked a late model white Holden Astra hatchback with the hazard lights on, on Toorak Road about 2.20pm on 10 May.
He entered the store and spoke to a staff member about a ring that had been on display in the window.
The staff member was showing the man the ring, he held it in his hand before running out of the store and getting back into the car.
The car was last seen travelling west on Toorak Road toward the city.
Investigators have released images of a man they believe may be able to assist with their enquiries.
Anyone with information is urged to contact Crime Stoppers.