As Donald Trump prepared to travel to Moscow five years ago for the Miss Universe pageant, he wondered whether he would run into Vladimir Putin. "If so," he wrote on Twitter, "will he become my new best friend?"
Today, as the Apprentice-host-turned-president gears up to meet with his ex-KGB Russian counterpart in Helsinki for their first summit, the world is asking a similar question.
Syria, election meddling and Ukraine will all be on the table in the talks, but much of the focus will be on the personal chemistry between the two men.
Trump has long expressed his admiration for the strongman leader, while US intelligence services allege Putin ordered Russian intervention to tip the 2016 US presidential election and push the brash billionaire into the White House.
In terms of temperament and style, the presidents could scarcely be more different.
While Trump speaks off the cuff and often angrily contradicts his own advisors -- or himself -- Putin is never caught off-guard in public and rarely raises more than an eyebrow to express his emotions.
Putin keeps up to date via thick folders of intelligence reports and press summaries, but Trump's advisors reportedly struggle to get him to read even the shortest of briefings.
And whereas the US president throws his opinions out via social media, his opposite number in the Kremlin does not even own a smartphone -- relying instead on domestic media to make his feelings known.
- Mano-a-mano -
But their differences will not necessarily prevent the pair from bonding.
"Putin has proven himself to be incredibly savvy at reading personalities and characters," said Alina Polyakova, a foreign policy fellow at the Brookings Institution in Washington.
"This is what he was trained to do, after all, as an intelligence officer and I think he's particularly been good at reading character weaknesses," she told AFP.
"He will praise Trump and try to bond with him in sort of a mano-a-mano way. Trump will be responsive to that tack," she added.
If this is the case, Putin will also have some genuine similarities to tap into.
The pair share authoritarian tendencies. After a recent meeting with North Korean dictator Kim Jong Un, Trump said he envied the way "his people sit up at attention" when he speaks and wished "my people" did the same.
They both prefer making surprise, unilateral decisions to getting bogged down in the business of dealing with institutions or checks and balances.
And the two men are nationalists who promised to make their countries "great again" -- Putin after the instability that followed the collapse of the USSR and Trump after what he saw as the decline of American industry.
They are also both wealthy, even if they have different ways of showing it.
Documentaries on Russian state TV emphasise Putin's ascetic lifestyle, but those in his inner circle have accumulated vast riches and critics say the president himself is worth tens of billions of dollars.
Trump, who uses a golden lift to get up to his New York apartment, is synonymous with ostentatious displays of wealth, though US media report he is worth billions less than he claims.
- 'Hit first' -
Putin was born into a working-class family in Leningrad -- now Saint Petersburg -- in 1952, before joining the KGB intelligence service in his 20s.
Trump was the fourth of five children born to a wealthy New York real estate developer. He later used what he called a "very small loan" of $1 million from his father to get started in the same business.
As young men, both future leaders had a tendency to get into fights. Putin has said he learnt to "hit first" on the streets of Leningrad and Trump's violent scraps with his high school classmates have been documented in US media.
In the 1980s, as Trump saw his eponymous business empire grow, Putin watched the Soviet empire crumble from the East German city of Dresden, where he had been posted as a secret service agent.
While Trump's family are at the core of his personal brand, divorced Putin guards his privacy fiercely and his two daughters have almost never been photographed in public.
Trump has broadcast almost every aspect of his life since his rise as a businessman to his emergence as a reality TV star in the 2000s.
But little is known about Putin, who glided up through officialdom before being handed the presidency by his predecessor Boris Yeltsin, aside from the crumbs he has fed Russian journalists over the years.
In an observation that could never be made of his US counterpart, he was described by one biographer, Masha Gessen, as "The Man Without a Face".
Russian dolls depicting Russian President Vladimir Putin (L) and his US counterpart Donald Trump are seen on sale at Izmailovo flea market in Moscow
Putin and Trump have exchanged gestures of respect but their countries remain divided on delicate issues
Putin and Trump have different styles but a lot in common, analysts say