BBC Sport is profiling 20 of the greatest Formula 1 drivers of all time. The BBC F1 team were asked to provide their own personal top 20s, which were combined to produce a BBC list. Veteran commentator Murray Walker provides his own reflections in a video of their career highlights, and chief F1 writer Andrew Benson profiles the driver. This week, number one - Ayrton Senna.
Death, perhaps inevitably, has lent Ayrton Senna's legend a romanticised sheen.
The greatness of the man and the brilliance of his driving are remembered easily, the occasional darkness of his psyche perhaps less so.
But it does Senna a disservice to honour only part of his legacy. The significance of his achievements cannot be properly understood without a full appreciation of their origins.
Probably no driver in Formula 1 history dedicated himself more to his sport, gave more of himself in the unbending pursuit of success.
Senna was a force of nature, a powerful combination of spectacular raw talent and sometimes terrifying determination.
He had the good looks of a romantic hero, a charisma that could quieten any room, the eloquence of a poet and a spirituality with which millions felt they could identify. His dark eyes were windows to a soul of complexity and volatility.
All that made him into a demi-god in his homeland of Brazil, and admired the world over like few sportsmen before or since.
But with that determination, and his own knowledge of just how good he was, came a sense of entitlement that was less attractive and which led him to take actions that put his own life - and the lives of his opponents - at risk.
At the height of their rivalry, one of the greatest sport has known, Alain Prost remarked: "Ayrton has a small problem. He thinks he can't kill himself, because he believes in God, and I think that's very dangerous."
Senna's discourses on the dangers of his profession, though, would suggest he was well aware of his mortality.
"You are doing something that nobody else is able to do," he once said. "(But) the same moment that you are seen as the best, the fastest and somebody that cannot be touched, you are enormously fragile. Because in a split second, it's gone.
"These two extremes are feelings that you don't get every day. These are all things which contribute to - how can I say? - knowing yourself deeper and deeper. These are the things that keep me going."
Few, if any, racing drivers have ever spoken like this, giving a glimpse into the philosophical demands of their job and - just as importantly - showing they are fully conversant with them.
Fittingly, Senna drove from the beginning to the end of his career as if he was determined to test the limits of human endeavour and physical capability.
Long before it became apparent that he was an extraordinary human being, it was blindingly obvious that he was an extraordinary talent in a racing car.
His record in the junior formulae meant his arrival in F1 was highly anticipated, and in his debut season, with the Toleman team in 1984, he did not disappoint.
At Monaco, his sixth race, came the first proper glimpse into the driver who would dominate his era.
In the pouring rain, Senna climbed up from 13th on the grid to close rapidly on leader Prost, only to be denied victory when the race was stopped at half-distance, with Senna on the Frenchman's tail.
After further strong performances, he was offered a drive with Lotus for 1985. Senna, showing the ruthlessness that would become all too apparent, took it, despite having a further two years to run on his contract.
The Lotus was not the fastest car that year, but Senna put it on pole seven times in 16 races. His first victory came in only his second race with the team - again in the wet, this time at Estoril in Portugal.
Two more years at Lotus established him as arguably the fastest man in F1, and in 1988 he joined McLaren, taking Honda engines with him, to make a super-team with Prost.
To be the best - and prove it to the world - was Senna's driving force. Prost, as the recognised yardstick at the time, was the man he needed to beat to prove it, and Senna went to the limits of both his ability and acceptability - and beyond - to do so.
The resulting rivalry has passed into legend. Prost's excellence drove Senna to new heights, and some of the things the Brazilian achieved as a result almost beggar belief.
His career coincided with the infancy of on-board cameras, and they bore witness to a commitment on his qualifying laps that was both awe-inspiring and chilling.
Most famous, perhaps, was a qualifying session at Monaco in 1988, when Senna took pole from Prost by a staggering 1.427 seconds. He later spoke of a kind of out-of-body experience, describing his driving in a metaphysical manner.
McLaren dominated the 1988 season like no-one has before or since - winning 15 of the 16 races, with Senna taking eight to Prost's seven, and clinching the title with a dazzling comeback drive in Japan.
But the relationship between the two drivers, always fragile and wary, broke down completely the following year after Senna reneged on an agreement not to pass into the first corner at the San Marino Grand Prix. Any trust there had been was gone.
The 1989 title was decided in a collision between the two at Suzuka in Japan, and by a controversial decision by Jean-Marie Balestre, the president of F1's governing body, to disqualify Senna from the subsequent victory that would have kept the championship alive.
The sense of injustice from that incident burned inside Senna for a year - until the following year's championship came to its climax, also in Japan.
This time, there was no debate about whose fault the resulting crash was. Senna, smarting from Balestre's decision not to move pole position to the advantageous side of the track and believing there was a conspiracy against him, simply drove into the back of Prost's Ferrari at the first corner at 160mph.
Senna painted himself as the wronged man, but in seeking to justify the crash he dissembled. "We are competing to win and if you no longer go for a gap, you are no longer a racing driver," he said, failing to mention that the move was never truly on. He finally admitted it was deliberate a year later.
The crash ensured Senna won his second title, and he added a third in 1991, founded on four straight wins in the opening races. One of them was among his greatest ever - holding on in the wet in Brazil with only sixth gear, pushing himself so far that he collapsed in agony afterwards.
Through 1992-3 he was generally helpless against the all-conquering Williams-Renaults of first Nigel Mansell and then Prost.
But he was never better than in the second of those years, his final season with McLaren. Raging against the odds, he took five superb victories, the zenith at Donington Park, when he was - yet again - on a separate level from anyone else.
Senna finally got his hands on a Williams in 1994, and he was expected to carry all before him. But with the car's driver aids all now banned, and a design flaw in its front wing, it was initially a handful.
It took all his genius to put it on pole for the opening race of the season in Brazil, but in the race he was helpless against the faster Benetton of Michael Schumacher and Senna suffered the ignominy of spinning out as he tried to catch the German.
He failed to finish the second race, too, knocked out at the first corner, and then at Imola, fighting to stay ahead of Schumacher, he crashed at the 190mph Tamburello corner.
He should have walked away - several drivers before him had done so after accidents at the same place. But a suspension arm pierced his helmet and caused fatal head injuries.
Senna's death at the age of 34 left behind memories of a multi-faceted and complex man who was so much more than a racing driver.
He took his profession to a new level of commitment and operated on a plateau beyond reach of his rivals at a time when the field was perhaps as strong as ever.
He preached morality but was prepared to abandon it in pursuit of ambition and his own sense of justice.
He talked eloquently of his own mortality, but tested its limits with his almost every action in a racing car.
All this, coupled with his humanity, character and intelligence, gave him and his sport an appeal to millions beyond its normal demographic.
Senna was, as James Hunt once put it, "a truly staggering talent".