This wasn't meant to happen.
Scotland fans were in dreamland after Caldwell's strike
Not in their wildest dreams could Scotland fans have hoped their side would beat the World Cup finalists.
But Scotland somehow managed to keep Thierry Henry, Patrick Vieira, David Trezeguet et al at bay during a pulsating, nerve-shredding and engrossing 90 minutes in a drenched Glasgow.
The French players looked the part in the warm-up.
Caressing the ball in the middle of the park and stretching like gazelles, it appeared they were from a different planet.
But it was the plucky Scots who, while giving their opponents more than a few inches in height, stood head and shoulders above the team ranked second in the world come the final whistle.
Worried Scotland fans flooded the radio phone-ins before the game to register their concern at the omission of Kris Boyd up front, to debate the merits of Barry Ferguson as captain and to question the fitness of Lee McCulloch.
The scene looked like a boxing ring, with a heavyweight champion ready to give the featherweight a clip round the ear
The fans' fears were compounded with news of Wales receiving a mauling at home at the hands of a rampant Slovakia.
In Hampden's media section before the game, journalists sat slack-jawed watching the TV as Wales were torn apart by the slick Slovaks.
There was little chat as the goals rained in, but those with notepads and laptops at the ready must have been privately thinking 'please don't let this happen to Scotland'.
Then it was time for kick-off. Fireworks and a Kasabian song boomed out the PA system to greet both sets of players in a riot of colour and noise.
As the smoke enveloped the stadium, the scene looked like a boxing ring, with a heavyweight champion ready to give the featherweight a clip round the ear.
Thierry Henry failed to breach Scotland's iron curtain
The opening exchanges saw Scotland on the ropes, as France broke with pace and menace.
Henry was unfortunate to see his free-kick rebound off the post, then off Scotland goalkeeper Craig Gordon's face and to safety.
The knot of France supporters, wrapped in scarves and ski-hats rose as one, ready to celebrate the start of the bloodletting. But Scotland survived.
A chorus of boos accompanied every French boot on ball, as the home fans sought to unsettle the artisans.
A few minutes later Henry had another chance from a free-kick.
But this time his effort was comfortably saved and he ended up on his derriere after slipping on the sodden turf. Scotland fans cheered and the moment eased the tension.
The French fans were stunned to lose a game they dominated
Fletcher won a 50/50 with Makelele after 12 minutes, which further emboldened the home fans.
Fourteen minutes later the Scots gave an "ole" for every pass the home side made.
Despite a Vieira header being ruled out for offside, Scotland's rearguard stood firm.
The ring of steel thrown around Gordon's goal remained intact. Scotland fans in the 52,000 crowd then sang Doe A Deer, and again, and again and again.
It was monotonous, but brilliant, and mirrored the stubborn nature of Scotland as they hunted the French in packs and refused to allow them near the penalty box.
A collective sigh of relief greeted the half-time whistle.
Scotland clinched a memorable win over their illustrious opponents
Bon Jovi's Living On A Prayer reverberated around the stadium during the interval - and the line "we're halfway there" could not have been more apt.
In the second half Henry looked menacing without firing on all cylinders and he seemed ill at ease with the ferocious but fair Scottish tackling.
Maybe the Glasgow rain had flooded his engine.
Elsewhere, Makelele was winning the "battle of the sixes" with his opposite Barry Ferguson.
However, Scotland's captain was not to be outdone and snapped terrier-like at the Chelsea midfielder's ankles at every opportunity.
Then the unthinkable happened.
Caldwell swept home a Hartley corner from just outside the six-yard box and suddenly Hampden was utter pandemonium.
All the nervous tension of defending on the edge of your box in the face of stiff French attacks suddenly exploded - Hampden was suddenly a raging sea of Lion Rampants, saltires and kilts.
The national stadium has its critics. But the atmosphere after Caldwell's strike was incredible.
France's coach Raymond Domenech looked like the loneliest man in the world, standing impassively in the technical area.
He couldn't have heard the French journalists typing away furiously on their laptops above the din, but he must have known the knives were being sharpened.
Gary Caldwell shows his relief at the final whistle
As the game wore on you got the feeling it was going to be Scotland's day.
Then the fourth official held up the board indicating there would be three minutes of injury-time.
The figure sucked the life out of Hampden. Three minutes seemed like three days.
By this time Sylvain Wiltord and Louis Saha had replaced the ineffective Franck Ribery and Trezeguet.
Willy Sagnol's dangerous cross deep into injury-time was smothered by Gordon inside the six-yard box. Relief.
Then - an explosion of noise. Full-time and three points against the World Cup finalists.
It wasn't great, it was amazing; incredible - it didn't seem possible. Fans were torn between hugging their mates and blinking in disbelief.
This is a rare feeling for a Scotland fan. One of football's 'big boys' had been given a bloody nose.
The French players trudged off the pitch, looking shell-shocked. They had the lion-share of possession and the best chances in the game.
But it was the Scottish featherweight who had delivered the knockout blow. And how the home fans loved it.