We have been promised a spectacle. A bona fide, lighters-in-the-air, feet-on-the-monitors moment in rock history - with the amps, naturally, turned up to 11.
The fierce contest for seats has seen millions of fans scrambling for just 9,000 pairs of tickets. These musicians are living legends, we are reminded, giants of their genre, reuniting properly for the first time in nearly three decades.
So whether or not you like their music, it is just as well that the act charged with matching expectations is Led Zeppelin.
Of all the embodiments of rock 'n' roll over-indulgence, this band must surely be the most notorious. Trashed hotel rooms, pseudo-Satanism, epic binges and unspeakable acts involving groupies - it is a template that, 30 years after their heyday, still makes Pete Doherty look like Aled Jones.
But, as ever, the group's music outdoes the offstage antics in terms of excess.
As Robert Plant, 59, struts on stage for opener Good Times Bad Times - the singer's garments not quite hugging his figure like they did in 1976 - it is clear that age has not wearied him.
He and his band mates' brand of weighty, ponderous, steamrollering proto-metal - essentially, Queen without the sense of humour - set the standard for 70s stadium rock in all its bombast.
Good Times Bad Times
In My Time Of Dying
For Your Life
Trampled Under Foot
Nobody's Fault But Mine
Since I've Been Loving You
Dazed and Confused
Stairway To Heaven
The Song Remains The Same
Misty Mountain Hop
Whole Lotta Love
Rock And Roll
Their heyday overlapping with punk, it is easy to see why they regularly earned critical maulings. Zeppelin were cited as a key example of all that had become overblown and self-important about the genre.
A key inspiration for the 1984 rock satire This Is Spinal Tap, Zeppelin specialised in portentous, if vague, lyrics about grand, mystic themes.
But after all the hype that has led up to the event, you suspect anything less than the full 70s stadium rock treatment would be an anti-climax.
The extended instrumental workouts. Jimmy Page's double-necked axe being wheeled out for guitar shop favourite Stairway To Heaven. The lighting rig descending during No Quarter to emphasise the music's deeply celestial importance.
The ecstatic crowd love it. There is a sense of genuine occasion. And little wonder.
This is a reunion in the truest sense of the word. Other alumni of the pop and rock canon who have reformed recently cashed in on the nostalgia market - the Spice Girls, Sex Pistols et al - have resembled little more than tribute acts to their younger selves.
But past reunions involving Page, Plant and bassist John Paul Jones have, by contrast, been low-key and rare. None have even come close to approaching tonight's scale.
The show was rescheduled after guitarist Jimmy Page fractured a finger
"There's no-one comes close to what they do," says Tony Harper, 50, who has driven from Middlesbrough to be here. "They're still the business."
"I couldn't believe I landed a ticket," says Carole Smith, 41, from Plymouth. "And when they came on stage I had to keep reminding myself this was really happening."
The event - a tribute to the late Ahmet Ertegun, the founding chairman of Atlantic Records - suggests the band are motivated by more than just the prospect of swelling their already inflated bank accounts. It is, of course, a neat touch that percussion is tonight provided by Jason Bonham, son of original drummer John Bonham, who died in 1980.
The group are at their most successful when, on songs like Black Dog and In My Time of Dying, the sparse, taut blues needs no dramatic emphasis - and demonstrates Zeppelin's influence on the likes of the White Stripes' Jack White.
And when Page strikes up the riff to Kashmir (Duh-duh-duh! Duh-duh-duh!) you remember why this band have earned such a passionate following.
Perhaps because they have kept the comebacks to a minimum, Zeppelin carry their advanced years better than most groups of similar vintage.
Plant, at 59, now exudes an aura of gravitas that lends authority to the band's more extravagant moments.
And Page - Mephistophelean with his black frock coat and explosion of white hair - is an equally commanding presence, an incongruous gardening accident which forced the show to be rescheduled notwithstanding.
The erstwhile disciple of Aleister Crowley even looks - whisper it - as though he is enjoying himself.
Nearly 40 years may have passed since Led Zeppelin formed. But for fans and band alike, the song remains the same.