You're on an epic journey with Alyx, racing the Combine through the wilderness outside City 17. The Citadel has been destroyed and lies massively across the horizon, with a twister of plasmic energy spiralling into the clouds. Kleiner says it's "the infancy of a superportal". G-Man is back. We learn about his relationship with Alyx. The Combine Advisors move to the fore. Breen's fate is unknown. Double-double-crossing Judith Mossman has a role to play. Dr. Magnusson, one of Gordon's Black Mesa colleagues, is leading an effort in White Forest to launch a satellite. Alyx and Gordon possess the means to access the Combine overworld. Hunters - the raptors of the Strider family - are tracking them. A new muscle car adds to the free-form feel and facilitates fast travel. The Antlion underworld beckons, and Antlion Workers are ready and waiting, corrosive phlegm on standby. Vortigaunts are fighting by your side. Their motivation should become clear.
And somebody's going to die.
Valve hasn't even loaded the game up for me yet, and I've already learned more than I did in the whole of Episode One. When I am wheeled next door, I'm shown six sections taken from the first two-thirds of the game. Wikipedia take note, programmer David Speyrer says they're still fine-tuning the chapters, "but I believe we ended up with six." Does that mean it's going to be another four-hour romp? In a word, no. "We're running at about six-to-eight hours in our playtests here. That's a first-time-through figure," says Speyrer. "It's really varied - you're always being confronted with new environments and situations. It gives it really an epic feel relative to Episode One." That scale won't just be apparent from the run-time, either; Episode Two is immediately impactful. When we grab Gordon by the WSAD he's still in the train carriage that he and Alyx rode away on at the climax of Episode One, only at this point it's lying on its end in a mass of wreckage at the foot of a valley. Clambering down, we find ourselves stuck neck-deep in water with no way out and no weapons. Fortunately Alyx is already outside. Even more fortunately, she's found the gravity gun, which she uses to prise off the door. "I forgot what a kick this thing has," she says, before handing it back. "When I couldn't find you, I kept... I know, I shouldn't have worried." What, no hug?
"The world state of Episode Two has changed considerably," designer Gautam Babbar tells us. "The Citadel's now destroyed." Ah yes, the Citadel. It's the first thing you see when you move over a small hill out of the debris from the train, which is not so much at the bottom of a valley as draped all over it, with sections still hanging from the massive bridge that links the two walls. It reminds me of The Cassandra Crossing. No time to point that out though, because the Combine portal that towers over Ground Zero in the distance is doing something. Bang, it releases a bubble of energy that races towards you and smashes into the valley, collapsing the bridge spectacularly. That's thanks to the new "cinematic physics system", which you may have glimpsed in trailers. Remember the bit in Episode One where you're pinned down in an attic by a Combine flyer, and bits of the floor keep getting knocked out, leaving a lattice of beams that shouted "you're in a game" like nothing else? In Episode Two, they would have just blown the entire place to pieces. "It lets us use a whole new style of special effects techniques for cinematic destruction sequences in real-time," says Speyrer. "You can go into a building and run around it and then the whole building gets blown up."
With the stability of the world in constant flux thanks to those energy bubbles - portal storms - there's every chance we'll be seeing this a lot. But before anything else happens, we're guided through a cave and into a communications outpost. "Dr. Kleiner and my dad are up north at an old missile base," Alyx explains, before climbing up some scaffold into the rafters to try and get things working. She knocks loose an electrical cable, which my trusty gravity gun is well-placed to return to its socket. "Not sure what I did, but it worked," she says. Gordon's typically modest. Kleiner and Eli Vance pop up on the vid-screen, and it's time for some exposition. Like Episode One, Valve wastes no time in explaining what's happening. "The raw discharge of the meltdown has been focused into a coherent beam of portal energy," Kleiner says, discussing the Citadel's present state. "What you're seeing is the infancy of a superportal." Which isn't good, because it puts the Combine on course to reinforce quite dramatically. If they do, says Eli, "it'll be the seven-hour war all over again, except this time we won't last seven minutes." What to do?