UPDATE 5.20pm: Assassin's Creed: Syndicate will launch on 23rd October for PlayStation 4 and Xbox One, and then later in the autumn for PC.
In today's reveal Ubisoft confirmed much of what we already knew - Syndicate is set in London, in 1868, and star twin brother and sister Jacob and Evie Frye.
The story once again has those pesky Templars causing trouble and persecuting the poorer folk - which you can corral into organised gangs of criminals - syndicates - to do your bidding.
Jacob is armed with a revolver, brass knuckles, throwing knives and an assassin gauntlet that includes hallucenogenic darts, a rope dart and a hidden blade. no more sword. throwing knives. You can also cause environmental damage to foes in certain places.
New gameplay showed how you can now nab a horse-drawn carriage and go racing around after your foes. It's like Grand Theft Auto but with horses - so a bit like Red Dead Redemption, then.
Overall, the game's tone seemed similar to Ripper Street or the Robert Downey Jr-starring Sherlock Holmes movies - slightly steampunk, rather violent and full of grime.
Meanwhile, a Guardian report has confirmed the earlier leak of two playable protagonists (Jacob and Evie), confirmed that there will be no co-op or multiplayer of any kind. London will apparently be 30 per cent larger than Paris' map.
Finally, there will be four special editions of the game, which include a number of extra missions, a season pass, an actual map, a figurine and any number of extra collectible items. See them below:
Assassin's Creed Syndicate editions pic.twitter.com/Ur9VgYdREw— lifelower (@lifelower) May 12, 2015
And see the first official gameplay here:
ORIGINAL STORY 3.30pm: Ubisoft is due to unveil this year's major Assassin's Creed game at 5pm UK time tonight - and you can watch the reveal on Eurogamer via the embedded stream below.
Where might it be set? Who will its new main character be? You'll have to tune in and find out! Or just read below, where we round up all of the leaked information so far.
Assassin's Creed: Syndicate (yes, really) will be released this autumn for PC, PlayStation 4 and Xbox One, reports state, and set in London.
You may have heard it previously referred to by its working title, AC: Victory. It's nothing to do with Syndicate the game, or Syndicate the YouTuber (that we're aware of).
Syndicate's name change from Victory is a shame - its previous title was a neat tie-in to the game's Victorian age setting.
Also V is the Roman numeral for 5, which would be the right numbering for this game if you forget about last year's AC: Unity.
Syndicate will be the first Assassin's Creed game set in a properly post-Industrial era. Think of London but with an impoverished working class, dirty living conditions and general despair among the poor. Now rewind around a century from 2015 and you're there.
Your new Assassin hero is named Jacob Frye, and from early concept art it looks like he carries a knuckle duster and eagle-topped cane alongside the Assassin's customary hidden blade. He'll also have a grappling hook-type device for swinging into action and be able to fight atop horse-drawn carriages.
But while Jacob will feature in the majority of the game's story, a new report has revealed a second playable protagonist - Jacob's sister Evie - who will co-star and be playable in the game's open world. Sort of like Batman and Catwoman in Arkham City.
It's great to hear about another female protagonist for the Assassin's Creed series, and impressive how soon this was implemented after last summer's PR gaffe.
The Fryes will be heavily involved in Victorian London's criminal underbelly. Some kind of tie-in with Jack the Ripper seems like too good an opportunity to miss.
Ubisoft has also hinted that the series will return to a greater focus on the game's modern day storyline in future installments.