Two days before the Scottish referendum, Tony Blair entered the campaign.

His plea for the Union came from neither side of the Border but from Crimea, where he was the guest of Victor Pinchuk, one of Ukraine's three principal oligarchs and the 255th richest man in the world.

He might equally have been with US billionaire Haim Saban, the 104th richest man in America, or Bernard Arnault, head of Louis Vuitton Moet Hennessy and the fourth richest guy on the planet. They are among the globetrotting plutocrats who fund his activities, styled as "old chums" by Francis Beckett, David Hencke and Nick Kochan in their investigation into the 10-year Premier's extraordinarily lucrative after-life.

The introduction to Pinchuk came from Bill Clinton - who was heard with respect bordering on awe when he addressed the Scottish Business Awards in Edinburgh two years ago. But Blair's private-jet itinerary seems unlikely to take in the country where he was brought up and educated any time soon.

Aside from fearing a "blood on your hands" Iraq protest, a UK charity event might expect Blair's fee to go - as Clinton's £200,000 did - straight to his African charity. Neither Tony Blair Associates (TBA), nor the Tony Blair Faith Foundation (TBFF), discloses any such information.

His other charitable arm, Africa Governance Initiative, says its aim is to bring "British standards of governance" to Africa. But Blair's own conflicting interests, if screened against the Nolan ethical code for public life he himself introduced as PM, may breach six of its seven principles, the authors suggest.

An opaque web of 12 legal entities - all under Blair's control - hides everything, including speaking fees said by one charity to "start at £500,000". In Qatar, one of the book's sources alleged, he earned "$5m for one meeting".

TBA's known clients, with guesstimates of deal value, include the Emir of Kuwait (£27m), Sheikh Mohammad bin Zayed Al Nahyan of Abu Dhabi (£1m a year), the President of Kazakhstan (£8m a year), JP Morgan ($4m a year), UI Energy which bought oilfields in Iraq, and LVMH. Commercial links investigated by the authors include dealings with such non-New Labour regimes as Libya under Gaddafi, Qatar, Rwanda, Burma and Azerbaijan.

Blair's corporate empire employs 200 and may have earned £54m in 2013. Tony and Cherie own 36 properties, including five overseas and two blocks of flats, and they could be worth £60m.

"Nothing is too grand for the Blairs," say the authors, who boggle at the pursuit of "wealth way beyond their needs", speculate that both experienced some financial insecurity in childhood, and suggest that the former PM "admires, and is dazzled by the very rich".

But while Clinton's wealth is (at present) even greater, and John Major and Margaret Thatcher both took hugely paid directorships with controversial US companies, all three are untainted by the conflicts engendered when Blair opted to become Middle East peace envoy for the Quartet (US, EU, Russia, UN). He needed it "to continue to feel like an international statesman and not just a businessman", Malcolm Rifkind is quoted as saying.

The public job enabled the fallen idol to step straight into the role of shadow statesman and fantasy head of state. He turned his two principal homes into clones of Number 10 and Chequers, and maximised an international network for his own, private, diplomatic consultancy.

While the unpaid envoy's official "one week a month" in the conflict zone is said to be typically "arrive Monday evening, leave Thursday morning", and has arguably borne little fruit, his frequent visits to the Gulf states have been highly productive - certainly for Tony Blair Associates.

The envoy can use the Quartet job as a "calling card", yet is bound by no code of conduct. If he worked for the World Bank, IMF or UN he would have to set out in full all commercial interests - as he would by taking the customary peerage.

When he left Downing Street (in high dudgeon), Blair claimed to Time magazine that his faith foundation was "how I want to spend the rest of my life". His seven-strong personal PR team claims the former PM spends "two-thirds" of his time pro bono, and that his commercial activities fund his philanthropy.

This dogged forensic examination, which had to battle a "huge communications department aimed at not publishing anything", a subject "who instructs his employees and adherents to give no assistance at all to so disrespectful a project", and fear induced by 20-page employee secrecy agreements, uncovers a more complex and disturbing picture.