The second series of gangland drama Underbelly is expected to be filmed in both Sydney and Melbourne.
The prequel to the hit TV show is due to start filming in the next couple of months, ahead of its air date from February 2009.
Nine is remaining quiet on the details, but a spokeswoman confirmed the story would be based in two cities.
"The new series is in the very early stages of development and will encompass storylines in both Sydney and Melbourne," a Nine Network spokeswoman told AAP.
"Production methods are still being discussed."
It's understood the series will focus on Vince Colosimo's character Alphonse Gangitano - known as the Black Prince Of Lygon Street - who was only in the first series for a couple of episodes before he was killed.
The 13-part first series was a dramatisation of Victoria's infamous underworld wars, which raged from 1995 to 2004, leaving 27 people dead.
It was based on the book Leadbelly: Inside Australia's Underworld, by John Silvester and Andrew Rule.
The second series is expected to focus on the background of the gangland figures.