Tonight's winner will face New Zealand in next week's final.

The All Blacks booked their spot in a record fifth final with a comfortable win over Argentina on Friday...

Confidence higher in the South Africa fans at the game than at home, it seems!

Mike Henson
BBC Sport at Stade de France

Image source, BBC Sport

England fans are heavily outnumbered by South Africans among the early arrivals at the Stade de France this evening.

Koeie (back row, middle) and Alan (back row, far left) have flown in from Johannesburg and Lydenburg with their families and were here last weekend as well for the quarter-final win over France.

They are confident of victory again, introducing me to the concept of South Africa's 'BMT'.

Not some sort of time zone, as I first thought, but 'big match temperament'.

They sniff some of the same stuff in Owen Farrell and are full of praise for Tom Curry and Ben Earl.

But mostly they sniff a final. "I don't think it will be too much of a stretch," says Alan as he ponders the Boks' potential winning margin.

"Maybe 20 points."

Sam Harris
BBC Newsbeat sports reporter

Image source, Ashleigh & Dylan

BBC Newsbeat caught up with Dylan and Ashleigh Gouws, a couple who moved to London from South Africa last year.

And surprisingly, the fans of the reigning world champions aren’t 100% confident.

“I’m slightly nervous for this game, England on their day can turn up and beat anyone,” Dylan says.

“I’m worried I might lose a few friends whatever the result is. There’s been plenty of banter between us.”

Ashleigh says the pair have some English friends who “have very kindly opened up their doors and let us in so we’ll be heading over there”.

“I’m usually quite cocky when it comes to South Africa games always thinking they’re going to win but this tournament I’ve had a few nervous moments for sure,” she says.

“For the semi-final though I’m going to be super cheeky and predict a 32-12 win for South Africa. We like that score a lot.”

Taj: This is England's toughest game of the tournament. This South Africa team is 8/10. If we can keep them quiet for 15 minutes, I believe we have a chance. It won't be easy, but we've been here before. Come on England!!

Jamie: I think if England play well, we should win. I think England to win by 5.

'Could' doing more heavy lifting than George Martin at a line-out there.

Bobby Skinstad
Former South Africa captain on BBC Radio 5 Live

Image source, Getty Images

There are a number of areas where England can be smart enough and physical enough. They have had different route to the semi-finals – but not easier. If you go man to man with South Africa you see outstanding rugby players.

Off-field machinations have got in the way of them being as organised as they have been in the past but a couple of performances and this team could be absolutely outstanding.

This loose trio from England would be competing to start in South Africa’s team to a man. I don’t think in any instance South Africa underestimate this England team in any way whatsoever.

Lewis Moody
Former England international on BBC Radio 5 Live

Image source, Getty Images

If you saw where England were 10 weeks ago when we were awful quite frankly, the Fijian loss (in a World Cup warm-up) gave us perspective.

Upfront is going to be key but England have to score tries. South Africa showed against France how clinical they can be so if England are going to win then the defence has to be strong, but they have to score tries and for me that’s the bit we haven’t seen from England yet.

South Africa probably should have it by 10-15 points but England have the capability, they have the players, and they have a coach who is prepared to apply the tactics to win the game.

The bookmakers have South Africa as heavy favourites tonight - and opinion among the pundits is split. But still largely on the green side of things...

Image source, Getty Images

In their five meetings with South Africa in the World Cup, England have won only once - a pool game on the way to overall victory in 2003.

South Africa have famously won two finals against England before, including four years ago when they came out on top 32-12 in Japan.

A week after demolishing New Zealand in sensational fashion, England were overpowered and contributed to their own downfall by making a series of errors that day. Have they learned a lesson?

Mike Henson
BBC Sport in Paris

Image source, Getty Images

England are the only team through to the Rugby World Cup semi-finals with a 100% record, progressing with five wins from five games.

They are unbeaten, but not undoubted.

Victories over Argentina, Japan, Chile, Samoa and Fiji have kept England's campaign purring steadily forward. Not all the wins have been convincing, but on each occasion they have ended up on the right side of the scoreline.

The caveat is that they have also been on the right side of the draw.

Now, the velvet rope drops and they bash shoulders with the tournament's big rollers.

It doesn't get much bigger than this. Well, until next weekend, anyway...

How highly do you rate this South Africa team? Where can England hurt them? Can anyone stop the All Blacks?

Fire away...

Image source, Getty Images

Standing in England's way are - once again - the champions. South Africa outmuscled and out thought England in the final four years ago, and just last week beat the hosts France in what was probably the best rugby union match I've ever seen.

The first 40 minutes were sensational. Steve Borthwick's side have a task on their hands that even Hercules would be looking to subcontract out.

Image source, BBC Sport

England: Steward; May, Marchant, Tuilagi, Daly; Farrell (capt), Mitchell; Marler, George, Cole, Itoje, Martin, Lawes, Curry, Earl.

Replacements: Dan, Genge, Sinckler, Chessum, Vunipola, Care, Ford, Lawrence.

South Africa: Willemse; Arendse, Kriel, De Allende, Kolbe; Libbok, Reinach; Kitshoff, Mbonambi, Malherbe, Etzebeth, Mostert, Kolisi (capt), Du Toit, Vermeulen.

Replacements: Fourie, Nche, Koch, Snyman, Smith, De Klerk, Pollard, Le Roux.

Referee: Ben O’Keeffe (New Zealand)

A blitz of energy, an early try and some nerveless kicking. Just like that, the champions were dethroned in Yokohama.

For much, if not all of the 1,456 days since England shocked the All Blacks in the semi-final four years ago a repeat trip to the final felt unlikely at best.

Image source, Getty Images

In the last 12 months alone Eddie Jones' star waned and eventually burned out, George Ford and Owen Farrell swapped midfield shirts more times than prime Frank Lampard and Steven Gerrard and France ran in seven tries in a record-breaking, humiliating romp at HQ.

Image source, Getty Images

Expectations were low heading into France this autumn. And yet, somehow, here they are.

England are one win away from a fifth World Cup final.

They couldn't - could they?