Three men who abducted and raped a teenager in Melbourne more than 30 years ago have been warned by police: "We'll be coming to get you."

Key points: The 18-year-old was abducted on the night of November 22, 1985

The 18-year-old was abducted on the night of November 22, 1985 The woman, who has since died, told police a man saw her being dragged into the car

The woman, who has since died, told police a man saw her being dragged into the car Police are offering a $350,000 reward for information leading to a successful prosecution

Susan (not her real name) was 18 when she was dragged from a South Yarra street into a car, then bound, gagged, blindfolded and taken to an unknown location, where she was sexually assaulted in a terrifying three-hour ordeal.

Her attackers have never been found, but Detective Inspector Steve Wilson from Victoria Police's Sexual Crimes Squad said fresh information had renewed hope of a breakthrough.

"In 2017 we were provided with some very credible information that allowed us to reinvigorate this investigation and as a consequence we believe that this is a very solvable incident," he said.

Police are offering a $350,000 reward for anyone who can provide information leading to a successful prosecution, and they have released footage of a re-enactment which they hope might jog memories.

"To the people out there who have committed these offences, we'll be coming to get you," Inspector Wilson said.

The woman was selling flowers on Chapel Street when she was attacked. ( Supplied: Victoria Police )

"It's only 30 years ago, so certainly we are looking with anticipation that these people are still alive and therefore we will be prosecuting."

On the night of November 22, 1985, Susan had been selling flowers to customers at restaurants, cafes and bars along Chapel Street, South Yarra.

Police say she returned to her car on nearby Bray Street to collect more supplies at about 10:00pm, which is when the abduction occurred.

She was grabbed by two men — one in a balaclava, the other in a stocking mask — and forced into a car where she was tied up and blindfolded.

According to Susan's police statement, at least one man saw her as she was being dragged into a white Holden commodore.

"Clearly we would like that person to come forward," Inspector Wilson said.

After being tied up and blindfolded, Susan was driven to an unknown location where another man was waiting. She was then raped repeatedly over the next three hours, before she was dumped in Richmond.

Police say it appears to have been a random attack, but the coordinated nature of the incident suggests they may have been serial offenders.

"It doesn't seem the usual first offending so … we would anticipate there may well be other offences that come to light," Inspector Wilson said.

"We also believe that there may well be a situation where these offenders haven't kept this to themselves."

The woman told police at least one other person witnessed her abduction. ( Supplied: Victoria Police )

Susan died in unrelated circumstances in 2008.

Police have also released a video interview with an unidentified friend who said the assault had a profound impact on Susan's life.

"She became less trusting of males in her life. She valued sex a whole lot less — she had a totally different outlook on relationships to the rest of us as a group of girlfriends," she said.

"It really did have a long-lasting effect on the way she interacted with males in the community and relationships that she had ever since then."

Her brother also appeared in the interview.

"She'd be grateful, she'd really appreciate it to be worked out and solved," he said.