When: Friday June 18, 20:00 BST
How to watch: ITV
It's the big one. Well, at least it is as far as England Scotland are concerned and it always has been.
The two oldest national teams on the planet have been doing this dance ever since they played the first international match in history all the way back in 1872.
Matches have become rarer as they years have progressed, but in terms of atmosphere and rivalry, there can be little doubt that England vs Scotland is the match in the group stage that no one is going to want to miss.
Previous three meetings
Scotland 2-2 England (Qualifier - June 10, 2017)
It's fair to say that things got a little bit crazy the last time these two sides met on the international stage - as things often can in 'auld enemy' clashes.
In all fairness, it all looked like it was going quite well for England when Alex Oxlade-Chamberlain handed them the lead with 20 minutes left.
Leigh Griffiths had other ideas, though, and he scored two sumptuous free-kicks in the 87th and 90th minutes to try and snatch a remarkable three points.
However, Harry Kane was not letting Scotland get away with that kind of nonsense, and he nabbed himself and England a leveller deep into stoppage time.
England 3-0 Scotland (Qualifier - November 11, 2016)
It was all a lot more routine for England in the other fixture in their 2018 World Cup qualifying group, although it was a very different team to the one we will be seeing at Wembley in Euro 2020 (as it will be for Scotland).
Daniel Sturridge eased England in front mid-way through the first half, and Scotland never really looked like getting back into it from there.
Adam Lallana and Gary Cahill added some gloss to the scoreline in the second half.
Scotland 1-3 England (Friendly - November 18, 2014)
Wayne Rooney was at the double for England back in 2014 in what was a laergely unremarkable international friendly.
Alex Oxlade-Chamberlain was England's other scorer, with Liverpool star Andy Robertson grabbing Scotland's solitary reply.
And of course…
England 2-0 Scotland (Euro 96 - June 15, 1996)
You didn't really think we'd let this slip by without mentioning this one, did you?
You know the story… football coming home, (old) Wembley sunshine, Shearer, Gazza, Scotland missing a penalty, Seaman saves, etc etc etc.
You don't need us to tell you about it. Just watch it and enjoy it - even if you're Scottish.
England trying to build on solid start
There weren't many people lining up to go over the top in their analysis of England's opening fixture win over Croatia, although perhaps that in itself is strange.
It was the first time England had ever won their first match of a European Championships, and there was a calm and confident authority about how it was done.
For England, that's new, and it highlights the degree of trust the public and media appear to have in this team.
The real question is whether England can build on that solid start and begin to go through the gears as the tournament progresses.
Scotland won't be an easy team to break down and it will likely be more frantic than any other match in the tournament, but if England are as good as we hope they are, they will find a way to win it.
Goalkeepers: Sam Johnstone, Jordan Pickford, Aaron Ramsdale
Defenders: Ben Chilwell, Conor Coady, Reece James, Harry Maguire, Tyrone Mings, Luke Shaw, John Stones, Kieran Trippier, Kyle Walker, Ben White
Midfielders: Jude Bellingham, Jordan Henderson, Mason Mount, Kalvin Phillips, Declan Rice
Forwards: Dominic Calvert-Lewin, Phil Foden, Jack Grealish, Harry Kane, Marcus Rashford, Bukayo Saka, Jadon Sancho, Raheem Sterling
It could only happen to Scotland
It was hard not to feel at least some sympathy for Scotland in their opening match against the Czech Republic.
They have waited 23 years to qualify for a major tournament and the second they do some Eastern European party-pooper produces a wonder-goal from the half-way line in their own back yard.
Yes, it could probably have only happened to Scotland.
However, the Scots also have every reason to remain optimistic. The very reason they are at this tournament after such a long absence is because they boast their strongest team for a very long time.
Goalkeepers: Craig Gordon, David Marshall, Jon McLaughlin
Defenders: Nathan Patterson, Stephen O'Donnell, Andy Robertson, Kieran Tierney, Greg Taylor, Liam Cooper, Grant Hanley, Declan Gallagher, Scott McKenna, Jack Hendry
Midfielders: Billy Gilmour, Callum McGregor, Scott McTominay, Stuart Armstrong, John McGinn, John Fleck, David Turnbull
Forwards: Che Adams, James Forrest, Ryan Christie, Ryan Fraser, Lyndon Dykes, Kevin Nisbet
England wins: 48
Scotland wins: 41
Is it just us or is there a real feel that this tournament might have Raheem Sterling's name written all over it?
The Manchester City man appeared to be barely clinging onto his place for the first match yet was the matchwinner, and there is just something about all of this that feels like it just might be his time.
Sterling is 17/4 to open the scoring again for England, and that is pretty good value.
You also though wonder whether set-pieces may be key, so keep John Stones in mind. He has popped up with World Cup goals before and he can be backed at 7/1 to score anytime.
As for Scotland, there is no Leigh Griffiths this time, and you feel their strikers may not get a lot of chances during the match.
A player capable of something spectacular may be an astute one to back, then, and John McGinn's 16/1 to score the first goal looks particularly tempting.