It wasn't just its exhaustive rounds of hearings around the country - Melbourne, Brisbane, Darwin, and Sydney - on topics from farming finance to financial planning. It wasn't even the long list of scandals exposed to a horrified nation - charging fees to dead people, blatant conflicts of interest, and taking $1 billion from customers in fees that banks were never entitled to.
What made it so fascinating, so heart-breaking, and so enraging was the procession of faces through the witness box, and the team of counsel gazing into the dark heart of banking.
Tearful victims, blank-faced executives, hapless regulators, and a couple of utter charlatans all had their day in court, watched by an audience of millions, and revealing - in their stories - the material to justify re-shaping the multi-trillion dollar financial services industry that forms a pillar of Australian life.
A Wunch of Bankers covers not just the big shocks, but the small moments - lost in the flurry of daily reporting - that reveal how companies have used the law, limp enforcement, and basic human behaviour to take advantage of customers.
Is there a phrase that judges how much life-insurance spruikers in call centres can terrify you about your impending death - and the grief-stricken ruins of an estate you'll leave for your bereaved family - while still being legal?
Yes, there is.
Was there a meeting in which a bank's executives ignored a warning of "Extreme" from its chief risk officer, to embark on an illegal scheme that accrued $3.6 billion in funds?
Mixed among the testimony are snippets from life on the road as the World's Oldest Debuting TV Reporter - not just driving five hours one-way to talk to a man who almost blew his brains out over a bank nabbing his $22 million estate, but explaining how journalism can only ever give you a glimpse inside complex issues.
In A Wunch of Bankers, Dan Ziffer bring out the colour and grit of the royal commission's proceedings, and explores broader issues raised by the testimony. A mixture of analysis, reportage, and observations, it is densely researched and compellingly written.