Police were told a 19-year-old boy from Hoppers Crossing was dragged from his car by an unknown man on Graham Street in Broadmeadows about 10.40pm on March 29.
The teenager ran from the scene, with the man chasing him before returning to the silver Mercedes Coupe CL180 and driving away.
The car was found dumped in Warnock Street in Broadmeadows the next day, but police have been unable to locate the offender.
Investigators have released CCTV footage to help track down a man they believe can help with their enquiries.
“Detectives have released CCTV of a male they believe could assist with their enquiries in the hope that someone can provide information on his identity and whereabouts,” a police statement read.
The man is perceived to be of Middle Eastern appearance, about 180cm tall, with a bald head and a beard.