The crowd had already had an incredible night, spirits were high, Ed Sheeran was performing his encore. Then he introduced Stormzy, and it all went to another level.
The guest appearance during Shape of You, the first of a two-song encore, sent the 40,000 crowd wild at Chantry Park.
There had been rumours of guest slots over the last week, but it was not until Sunday night that one of those finally materialised.
It was a brief cameo by Stormzy, who headlined Glastonbury only a few months ago, performing alongside his friend Ed for just one song. But that was enough for fans, who were buzzing.
It was another triumphant night for Framlingham star Ed, who will complete his record breaking Divide tour on Monday night at Chantry Park (and many will now be wondering if there are any more surprises planned then...).
He's amassed so many singalong hits over the last decade, and he treated fans to a mix of new and old material.
The layers of sound Ed can achieve with just his guitar and loop pedals is extraordinary.
The stage and screens were spectacular. The songs uplifting. His warm, humble personality is engaging - it's hard not to feel pride in such a likeable Suffolk bloke conquering the world.
He tells the crowd: "In Suffolk, being awkward is embraced and loved."
His show has distinct changes of pace. The finale to the main set - Sing - is a highlight of the night.
But it's the encore, and that surprise guest, that everyone will be talking about.
Other special mentions from tonight's gig go to Salvador - a young, four-piece indie band from Framlingham who sounded fantastic during their short set and seemed to love every minute of it. Magic.
Lewis Capaldi mixed powerful songs with humour for his first, very welcome appearance of the weekend.
He frequently had the crowd laughing out loud with his dry, playful humour, at one point saying: 'I sing sad songs. This one may sound happy, but trust me - it's depressing.'
And The Darkness were brilliant. The Suffolk rockers brought a sense of fun, delivered some terrific songs and brilliant exchanges with the crowd - "Rick" became an unlikely star of the set after a sing-off with Justin Hawkins, who is a wonderfully entertaining frontman.
And a final word on Chantry Park. What a great venue. What a thrill to be able to see a show of this scale in Ipswich.
Organisation has, from my experience and judging from the feedback I've seen elsewhere, been really excellent.
How great would it be to see gigs like this in Ipswich every summer?
And I can't remember the last time an event or occasion brought such an incredible feelgood factor to Ipswich and Suffolk (probably Ipswich Town's promotion nearly 20 years ago).
For now, let's just settle for this weekend; Ed's homecoming, and gigs that will be remembered for many years to come.
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