Her book, Killing Fairfax, about the bloodsport in the Australian media industry, is also part of the much bigger digital story that has transformed the global media business in the past two decades. What gives the book legs for the New Zealand reader (apart from the animosity bordering on hatred which drives some of its principal characters) is the proximity of the action - mostly across the Tasman but with occasional plays in the local marketplace - together with the familiarity of many players: the 1987 Rugby World Cup-winning captain David Kirk, who was in the hot seat at Fairfax for three turbulent years, and the glimpse it provides of those two next-generation tycoons, Packer and Murdoch the younger.
On the phone from Sydney, Williams observes: "Both of these men were raised from the cradle to see Fairfax as not only the competition but the enemy."
To them, Fairfax, its wealth underpinned by the motherlode of classified advertising, was a "ghastly character" they could not get near.
"Their fathers always craved to get inside the Fairfax classified business. Both Rupert and Kerry were always covetous of the classifieds.
"When the sons found the opportunity to get in on the second floor, they seized it with both hands."
James Packer, in particular, "expressed a desire to use those investments to take revenge and damage it (Fairfax) in every way he could", remarks Williams. "It was as visceral as that."
As Packer and Murdoch prospered, partly by design and sometimes by inspiration, the two young risk-takers dealt grievous blows to the Fairfax publishing business. Seven years ago Fairfax had a market capitalisation of A$9 billion. Last month, reports Williams, the combined value of its assets was around A$1.3 billion ($1.5 billion).
Unsurprisingly, it is open season for writers on the weakened house of Fairfax. Williams' book, with its insider access to the pivotal figures in a monumental business failure, is published today. Colleen Ryan, a former Fairfax editor, was out of the blocks last month with tell-all Fairfax: The Rise and Fall. Yet another take on the tale, by yet another Fairfax luminary, journalist Ben Hills, is rumoured to be in the wings.
The publishing interest is stoked partly because for decades powerful public interest journalism has run in Fairfax newspapers. Its mastheads - the Age in Melbourne, the Sydney Morning Herald and the Australian Financial Review have produced page after page of in-depth, quality reportage, year in and year out. Up until a few years ago the titles employed as many as 1,500 journalists. The destruction wrought in the past decade means the head count is falling, and the papers shrinking. Pay walls are going up, access to digital editions comes with a price tag but the scale of the financial damage means questions persist over whether readers will continue to be served by a publisher with a proud reputation for fearless, independent journalism.
Two flagship mastheads - the Age and the SMH - have shed as much as one third of their circulation in the past three years as readers devour their content online. The company's share price yesterday was A52c. In the past 12 months it has been as low as A35c.
This painful, decade-long decline, from being one of Australia's most powerful and illustrious institutions, to a point where Fairfax's survival is not a given, is the thread running through Williams' story, propelled by the ruthless work of Packer and Murdoch.
We first meet the princelings in a private lunch room at an upscale Sydney restaurant. The date was August 16 last year. Williams was there too, and reports how the pair toasted the pain Fairfax was feeling.
"You know," says Packer," I think we killed Fairfax." Replied Murdoch: " I think so too."
They didn't do it alone. Mis-steps and indecision by Fairfax directors scorched the company. The story of Packer's prescient investment, the online job company Seek, is a salutary one.
Though he shared his father's loathing of their great media rivals, James saw revenge as a dish best served by competition. Writes Williams: "Packer was convinced the Fairfax classified print advertising business was going over a cliff. And that was something he wanted to be part of."
The courtship between Packer and Seek's owners took a few months. James Packer stayed close to the action throughout, "checking that no one was beating them up".
In fact, Fairfax was lurking around the start-up, but not with great intent. Even though the recruitment site was starting to get traction, with its value rising tenfold, and while the board was alert to the "online threat to print", Fairfax executives fatally stayed their hand.
"The deal Fairfax had needed to protect one of its three massive revenue categories was lost. Allegations of complacency, arrogance and lack of foresight would and could be thrown at the company in years to come," writes Williams.
Packer bought a 25 per cent stake for A$33 million. Years down the the track he quit his stake for a staggering A$440 million. Late last year Seek had a market capitalisation north of A$2 billion - twice that of Fairfax.
Lachlan Murdoch's good fortune was to buy a chunk of virtual real estate for a song, and then watch as the numbers grew as if by magic. He staked A$2.25 million in cash and pumped the investment with contra deals, using the power of News Ltd to promote the website realestate.com.au.
All up, Murdoch tipped A$10.25 million into the online start-up, saving it from the dotcom graveyard. By February this year, 12 years after the deal was wrapped up - once again after Fairfax executives turned their backs on the chance to take a stake in a rival minnow - realestate.com.au, or REA Group as it had been renamed, was an Australian monster. Its market capitalisation was an astonishing A$3.4 billion. News Corp owned 60.7 per cent, more than A$2 billion.
"It was the deal of the decade in Australia's online space," writes Williams. Fairfax had missed the boat with jobs, now it was left behind with property: "Twice Fairfax had missed out on taking control of some of the greatest online advertising companies in Australian history."
For all the failures by Fairfax executives and directors to stop the rot, Williams feels its board made a dreadful blunder in waving goodbye to David Kirk. Appointed chief executive in late 2005, the New Zealander raised eyebrows with an aggressive buying strategy, paying $700 million for Trade Me and steering a merger with Rural Press, a cashed-up publisher with a vast reach into Australia.
Trouble for Kirk arrived with the Rural Press purchase in the form of its top dog, chief executive Brian McCarthy. Unlike the neophyte Kiwi, McCarthy had deep newspaper experience. The hard-nosed Australian became Kirk's deputy but it didn't take long for divisions to surface.
Kirk, says Williams, was a fast learner. He could see how desperately Fairfax needed to diversify revenue streams, but he was being "white- anted" by enemies within the citadel. "It became war," says the author, "over power and ego."
Insider details spewed out of Fairfax, designed to either damage Kirk or burnish the Rural Press side of things. Eventually the conflict reached the board, where there could be only one winner.
Says Williams: "It's my view he was a very significant loss to Fairfax." Investments Kirk pushed - along with the $1.1 billion purchase in New Zealand of INL, steered through by Kirk's predecessor, Fred Hilmer - had helped keep the company afloat. "To me the tragedy of those years was when Fairfax didn't buy one of those pure-plays [the online classified sites] when it could have. We are still a strong company but we are a fraction of the size we were.
"My lament is we could have been on top of everything had we invested in those pure-plays. I don't want to suggest the company is gone. James Packer and Lachlan Murdoch have done their best to kill it off but we also did the job ourselves by failing to get on to those investments."
Of the future, Williams, who is back at her Financial Review desk, covering the Federal election, says the company appears determined to protect its reputation for strong journalism. "The fact someone like myself can write a book like this - in effect a searing exposé of past management failures and losses - and go back to work, well that says a lot about the company and its commitment to independent journalism."
• Killing Fairfax: Packer, Murdoch & The Ultimate Revenge by Pamela Williams (HarperCollins $49.99).