"Senna" - the award-winning 1995 documentary about the career of the Brazilian icon
Michael Schumacher may statistically be the greatest Grand Prix driver who ever lived, but to many who watched Ayrton Senna's career no-one can equal the brilliant Brazilian.
Senna's greatness does not lie in statistics, impressive though his career record is. It is embodied in the irresistible force with which he dominated an era of Formula One.
Senna's death on 1 May 15 years ago changed F1 forever, but his life also had an indelible effect.
The same moment that you are seen as the best, the fastest and somebody that cannot be touched, you are enormously fragile
In many ways, it was a negative one.
Senna's single-minded pursuit of success led to an uncompromising driving style that verged on dangerous, an approach since followed with conspicuous success by Schumacher.
But, to many, Senna also redefined what was possible in an F1 car.
He had a rage to win married to an ability that some would argue has never been equalled.
Senna dominated his cars every bit as forcefully as he did his rivals, employing a unique driving style to drag them to levels of performance their designers scarcely believed possible.
Perhaps the ultimate example of this was in qualifying for the Monaco Grand Prix in 1988, when Senna was in his first year at McLaren-Honda as team-mate to Alain Prost.
Then it was Prost who the other drivers measured themselves against, and establishing primacy over the Frenchman was initially Senna's number one goal.
Monaco, where Senna went on to win a record six times, gave him a chance to demonstrate his superiority.
Toleman, Lotus, McLaren, Williams
21/3/60 (Sao Paulo, Brazil
1/5/94 (Imola, Italy)
In qualifying, he set pole position with a lap 1.4 seconds faster than Prost managed in an equal car, and afterwards spoke in ethereal terms of an almost supernatural experience in reaching beyond his conscious self while driving.
The rivalry between Senna and Prost grew into the bitterest the sport has ever seen, and each man to a degree became defined by it.
But Senna had marked himself out as something special long before he went head-to-head with his greatest rival. His potential was obvious even before he reached F1.
In 1983, the Williams team gave the then up-and-coming Formula Three driver a test in their Grand Prix car, and within 40 laps he had taken it around Donington Park faster than its regular drivers, including reigning world champion Keke Rosberg.
Unfathomably, team owner Frank Williams did not offer Senna a contract, and it was to take him another decade before he had the chance to sign him again.
Classic F1 - Senna highlights
Instead, Senna moved to the midfield Toleman team and immediately made waves, being denied victory in torrential rain at Monaco, his sixth Grand Prix, only when the race was stopped before half distance because of the poor conditions.
His ability was already frightening his rivals, to the point that one said it was appropriate Senna's name had laxative connotations because that was the effect he had on him.
At the end of the year, showing the single-mindedness which was to become familiar, Senna walked out on a three-year contract with Toleman and joined Lotus, then one of the top teams.
Senna and Prost fought out a battle of such intensity that onlookers feared for their lives
His first win came in only his second race with them, Senna using all his peerless ability in the rain to make his rivals look flat-footed at the 1985 Portuguese Grand Prix.
Five more wins followed in three years at Lotus, but Senna saw the team's decline coming before most, and moved in 1988 to form a super-team with Prost at McLaren.
For three years - two as team-mates and one after Prost left to join Ferrari - the two fought out a battle of such intensity that onlookers feared for their lives.
It certainly drove Senna to new extremes. After one particularly frightening incident, Prost told Senna that if he wanted the title badly enough to die for it, he could have it.
Senna did sometimes appear to be putting his ambition ahead of his instinct for survival, most notably at the Japanese Grand Prix in 1990, when Senna secured the second of his three titles by driving into the back of Prost's Ferrari at 160mph, taking them both out of the race.
Throughout all this, Senna's breathtaking talent was in vivid relief. But if his driving was captivating enough, he was equally remarkable out of the car.
Senna was blessed with the good looks of a romantic hero, and his dark eyes were mirrors to a soul of complexity and surprising vulnerability.
This combination was made all the more powerful by his willingness to discuss the risks inherent in his job.
Deeply religious, Senna seemed sometimes to be overwhelmed by fatalism about the danger of his chosen profession.
Senna's determination to win took him to new extremes
His charisma was magnetic - he could hold in spellbound silence a room of hundreds of hard-bitten journalists - and his intellect, expressed with poetic eloquence in several languages, was formidable.
"You are doing something that nobody else is able to do," he 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."
When Senna joined Williams for the 1994 season, his position as the king of F1 was unquestioned. The team had dominated F1 in 1992 and '93, and Senna was expected to canter to the title.
But Williams' car initially had a serious design flaw, and only Senna's super-human ability put it on pole for the first race in Brazil.
In the race, though, he was flat beaten by Schumacher's superior Benetton, and Senna suffered the ignominy of spinning in his chase of the German.
Anyone wondering how much of that performance Senna dragged from within only had to look at his team-mate Damon Hill, whom Senna had lapped by half distance.
Senna went to Imola trailing Schumacher in the championship and desperately needing to win.
Already it was clear that one of F1's great rivalries was in the offing, the young pretender challenging the supremacy of the veteran master, who was determined to hang on to his position.
But as Senna headed into the Tamburello corner at 190mph, with Schumacher just over a second behind, something went wrong.
The Williams speared off the road and hit a concrete wall, still travelling at 137mph.
As fate would have it, a front wheel was knocked back towards the cockpit and Senna's helmet visor was pierced by a suspension arm. If the wheel had missed him, he would have stepped from the wreck unhurt.