This is the first Ashes Test with everything: a news-grabbing, fluctuating, nerve-stretching and morally tortured affirmation that five-day cricket between England and Australia can reach the parts no other rivalry involving bat and ball can hope to touch.
The best news of all, from an excitement point of view, is that this series will bring no easy extension of England's dominance from 2009 to 2011.
Four days of mesmerising action have spilled over into a fifth day that appeared inconceivable when 14 wickets fell on Wednesday, and both sides seemed too nervous to make it more than a perfunctory affair.
Just as English nerves were beginning to jangle with Australia on 84 without loss, Alastair Cook's bowlers emerged from their trance to remove six batsmen for 80 runs.
Ah well, they must have thought, at least we still have Ashton Agar to come in and smite the ball. As the evening beckoned Agar strode across the turf with willow in hand again not as the dazzled kid any longer but Australia's rescue man, after a dramatic spell of three wickets for three runs in 18 balls.
Michael Clarke, Steve Smith and Phil Hughes were all returned to the pavilion by Stuart Broad and Graeme Swann, who trapped both Smith and Hughes leg before.
Joe Root took his first Test wicket as a bowler, too the hapless Ed Cowan. At stumps Agar and Brad Haddin were still there with Australia 174 for six, still needing 137 to win.
The crowd poured out exhausted by the stress. Back on day one - it feels like years ago - Agar was still a symbol of Australian desperation: a beach boy borrowed from Henley and the Home Counties League to dislodge Nathan Lyon. The cognoscenti knew better. They knew he could bat, knew he could bowl.
But to most here at Trent Bridge he was just another leap in the dark post-Shane Warne. He looked like somebody's son who had been called off a shift behind the bar to make up the numbers. Receiving his baggy green cap from Glenn McGrath, Agar was positively bashful.
Maybe, in retrospect, that was the moment the spirit of the Ashes confirmed its attendance. This Australia side are a mass of frailties overlain by renewed unity and intent. On paper their starting team would frighten no one. Yet they have already lodged a claim to be remembered as overachievers.
There are four more Tests to play out before we can measure the character of the protagonists. But both are committed to entertain us, sometimes without really intending to. In a ludicrously congested calendar, in which cricket risks diluting its own worth by over-supply, each side has renewed its vows to The Ashes.
On this evidence, there could be no danger of this generation of cricketers treating it as just another fixture. The Saturday was another Alton Towers ride.
England resumed at 325 for six with Ian Bell's innings being hailed as the finest of his career. He completed his 18th Test century to draw level with Michael Vaughan and David Gower, but then fell to Mitchell Starc as the England tail began to fall away.
Bell's noble knock of 109 and Broad's controversial 65 were a riposte to Agar's 163-run partnership with Philip Hughes on Thursday, which featured a world record 98 for a No 11 from the younger of the batsmen.
Agar's spectacular emergence as an Ashes fairytale seemed to bring all the romance of 131 years flooding across Trent Bridge. It added a human touch to the conflict and inspired Agar's fellow Australians.
The next day he discovered the other side of this ancient feud, tossing up a ball which Broad thick-edged on to Haddin's gloves and then into Clarke's palms.
Agar, who took the wickets of Cook and Jonny Bairstow in the second innings, thought he had snared Broad as well. But umpire Aleem Dar missed the deflection, Broad declined to walk and social media split between those who thought Broad a rogue and a larger group who argued that few cricketers 'walk' these days and that players should be policed by the umpire and not themselves.
Nobody should under-estimate the power of a moral firefight to intensify interest in a piece of sport. If you can watch a good game, then great. If you can argue about it as well (and make your voice heard) then so much the better.
By then the technology ball had already been kicked around for a day. Jonathan Trott's dismissal on review for lbw after the umpire had given him not out showed up cricket's strange reliance on Sky for justice. The summer game is dependent on a commercial television station for the Hot Spot system that was otherwise engaged when Trott was adjudged to be out.
There will be grudges and gripes aplenty when the two parties reconvene at Lord's. England will take a long look at Steve Finn, who was ignored by Cook until the 29th over, and demand more with the bat from Root and Bairstow.
Equally Andy Flower can reasonably expect a more even performance from England second time round, now that this first encounter has been placed high alongside the 1982-83 Melbourne Test, which England won by three runs after Ian Botham had completed the 1,000 runs-100 wickets double against the Baggy Greens.
Australia, the sick man of world sport, are here to fight, here to save their country and themselves. Somehow they are able to carry Ed Cowan's reckless batting at No 3 and still maintain a challenge. There is no change to the early sense that their top seven batsmen lack the quality to outscore England over five Tests.
With only four scores over 50 in either innings to date, they look a vulnerable bunch by the standards of the last 20 years. But what a captivating follow-up to Murraymania and Lions euphoria.
The 2005 and 2009 series here in England will take some beating but this one is heading in the right direction. It will be scrappier, more desperate, at times, but we can cope with that, given the magnetism of the last four days here beside the Trent.