Yanis Varoufakis, handed the potentially explosive role of finance minister in Greece's new anti-austerity government, is known as "Dr Doom" over his stance on the country's deep economic woes.
Varoufakis, who has dual Greek and Australian nationality, believes the shattered country can never begin to recover until its massive international rescue package is completely renegotiated.
Varoufakis, a shaven-headed 53-year-old economist who has taught at universities including Australia, England, Greece and the United States, is already a frequent interviewee around the world and highly active on social media.
Though a first-time minister, not to mention a rookie parliamentarian, he will spearhead the bailout renegotiation talks with Greece's European Union partners and the International Monetary Fund that already promise to produce sparks.
"It is time to speak the truth about the unsustainability of the major denial with which Europe treated the bankruptcy in its midst," Varoufakis said in a pre-election interview with Britain's Channel 4 television.
Varoufakis, who has the build of a rugby player, spent his early academic career in England, at the universities of Essex, East Anglia and at Cambridge.
"My break from Britain occurred in 1987 on the night of Mrs (Margaret) Thatcher's third election victory. It was too much to bear," he writes in his extensive English-language blog.
Varoufakis moved to the University of Sydney, living in Australia from 1988 to 2000. He retains Greek and Australian citizenship.
The call of Greece proved too strong eventually, and despite having a daughter from a relationship in Australia, he returned to teach at the University of Athens.
Varoufakis was one of the first to warn of the risk that Greece could default on its massive debts, which have now swelled to more than 315 billion euros ($A448 billion).
The approach earned him the nickname "Dr Doom".
Although not a member of Syriza, the party of new Prime Minister Alexis Tsipras, Varoufakis was invited to work closely with the left-wingers.