A source from one station says "everyone will open their chequebooks" for what will "obviously be the interview of the decade". The Australian public's intense interest in the case – in which Corby was jailed in 2004 after being caught smuggling marijuana into Bali – has led network executives to forecast a huge audience for the broadcast. Most expect it to out-rate previous high-profile interviews, including those with landslide survivor Stuart Diver and mine collapse victims Brant Webb and Todd Russell. The pair were paid $2.6 million by Channel Nine's then-owner PBL, prompting the agent who negotiated that deal to predict Corby could net almost $3 million. Yet one station insider insists that free-to-air channels "simply don't pay that kind of money any more", suggesting a likely fee around $1 million. (Proceeds of Crime laws may prevent Corby from receiving the money directly.) With the 36-year-old edging closer to release – having obtained a new Australian passport this week and confirmation she can serve her parole in Indonesia – the networks are now racing to sign her. But for the prisoner and her family, the highest price is no guarantee of a deal. According to one TV producer who has dealt with them, they have "long memories" and are wary of accepting offers from those they perceive to have burnt them – or intend to burn them.

Traditionally, Seven has been the Corbys' network-non-grata. In 2008, Schapelle's sister Mercedes received a large payout after a jury found she had been defamed by Today Tonight. This worked to Nine's advantage until the station commissioned a telemovie "inspired" by the book Sins of the Father, written by Fairfax journalist Eamonn Duff. According to one Nine staffer, this displeased the Corbys, who dislike the book. Despite the fact that Nine's news and drama divisions operate independently, those close to negotiations say it could be enough to swing the deal in Seven's favour. A spokesman for FremantleMedia, producers of the soon-to-screen telemovie, says Duff's book is just "one of many source materials used in the development of the script", which is an "original work". "I was unaware the family had publicly responded to the telemovie," the spokesman says. "If they have, it certainly had no impact on the development of the script." Naturally, Seven is capitalising on the family's rumoured nervousness about Nine's movie – and stressing that the senior staff responsible for the Today Tonight drama of 2008 have since left. So far, the strategy appears to be working. Schapelle's mother, Rosleigh Rose, even allowed the network to fly her to Bali recently.

Indeed, Nine now considers itself the underdog, according to multiple sources, despite promising to match any offer from Seven. The dark horse in this bidding war is Channel Ten, which hopes to reverse its ratings slump, in part, by reinvigorating its news and current affairs offering. Securing the exclusive Corby interview would be a major coup, and incoming news and current affairs chief Peter Meakin is said to be keen to make an offer. Yet with Seven enforcing a "non-compete" clause after Ten poached him last year, there's nothing he can do until he starts in February. In the meantime, it's up to other Ten executives to chase the deal. Of course, both Seven and Nine have been reminding the Corbys that Meakin was running Seven's news and current affairs division when Today Tonight defamed Mercedes. The fact that Ten's rivals have deeper pockets does not help its chances. And whichever network gets the interview will have to walk a fine line. Those familiar with Indonesia's legal system say the courts are unlikely to impose any gag orders on Corby during her parole, giving the interviewer free rein. Viewers will therefore expect rigorous questions but a too-tough stance could be seen as exploiting her. Having suffered severe depression during her imprisonment – and if Corby's mental state is as bad as reported – the interview could be difficult to conduct and may not occur until some time after her release.

All three networks declined to comment but a source from one says the interview is not considered "make or break" for any station. Even if the cost and content is shared across multiple programs, or with a print outlet, it will fill a few hours' airtime at most. While this helps a network's "brand", the source explains, viewing habits tend to return to normal within 48 hours. But the interview itself will be a boon for the winning station. "They could have [Corby] reciting the bus timetable and the whole country will still tune in," says another network staffer. "The curiosity factor is enormous. No matter what you think of her or the case, you'll want to see what she looks like and hear about prison and all the details. Everyone will watch." - with Michael Bachelard mlallo@fairfaxmedia.com.au