This unlikely success brings us to the point of Fink’s work, which is to convincingly demolish various attacks on Ellis’ reputation, especially the self-serving accusations of treacherous dealings, first with the Nazis and then the Soviet Union, made by a phalanx of bitter, or simply gullible, “insiders”.

Fink’s bile is directed, though not exclusively – his blunderbuss peppers a host of dubious characters – at ex-MI6 spook Peter Wright, the publication of whose improbable “memoir”, Spycatcher, was famously defended here by Malcolm Turnbull in 1988. (Turnbull was in no way party to Wright’s ugly character assassinations of Ellis and others – his case was a straightforward defence of the right to publish.)

Ellis rose very high indeed in the intelligence world. He was to advise the Americans on setting up the CIA. He was instrumental in establishing both ASIO and ASIS in Australia. There is no evidence to suggest that he was a double or even triple agent, apart from the spurious allegations and suppositions put forward by best-selling writers such as Chapman Pincher and Wright.

It was all nonsense, if Fink is to be believed, and I think he can be.

He nails Pincher, one of Ellis’ most libellous accusers, for blatantly conspiratorial malarkey. “Pincher’s slackness [in his 1981 Their Trade Is Treachery] was a harbinger of the sloppy journalism that would become the norm in the internet age, when research and due diligence would become secondary consideration to publishing as quickly as possible.”

Yes, Ellis, who died in 1975, was interrogated in 1966. Nothing of any substance was found. But the mere fact that he’d been questioned spawned an orgy of bestselling “exposes”, penned for profit by men who had never felt at home with truth or loyalty.

Fink’s comprehensive exoneration, while as complex as the subject demands, is written by a fellow who clearly values both.

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