A 21-year-old man sitting in his unlocked car in Potter Street, Dandenong, was robbed at knifepoint.
The man was parked outside a vacant block about 9.55pm on June 7 when a man told him to get out of the car or he would be killed.
The robber stole the car, which was recovered in Pickett Street, Dandenong, several days later.
Contact Crime Stoppers on 1800 333 000.