This particular bit of the environment overcome, Lara heads outside the temple and across a Mayan ballcourt. She stops at a turnstile above a pair of giant gates set into the floor. The relics she's collected will allow her to open the gates - which, it turns out, are the gates to the Mayan underworld. This is what the game's subtitle refers to; not thankfully, any nonsense about Lara "going dark" and dealing with mobsters or drug dealers.
"Underworld has nothing in common with Angel of Darkness," says Van Rompaey. "If Tomb Raider: Underworld comes across as darker it's not deliberate. It's more to do with the fact that she is travelling to underworlds, places of the undead. Therefore it has a more mature tone and naturally will feel darker."
Eidos's Kathryn Clements says she doesn't want to give too much of the story away, but "it's safe to say Lara will be going to multiple underworlds throughout the game". Not just real-world locations, then? "No. The guys at Crystal have let their imaginations go. They're taking Lara to places she's never been before, places people will find surprising."
According to Bill Beacham, "Underworld is more mythology- than archaeology-based. I think it's important to have a grounding in reality; you can see that with the Mayan temple. But you have to go beyond that."
On her bike
This is where things get really interesting - with the potential for exploring fantastical environments and fighting off mythological creatures. Unfortunately, this is where today's demo ends. There's only time to show us Lara's new motorbike, said to be much improved and more useful.
It's got gears and can do everything a real motorbike can, including donuts and wheelies. It's also "much more integral to the levels", says Beacham. "It's one of the tools Lara has in her arsenal of gear now. If you want to get from A to B quickly, that's what the bike's for. It also has other functionality we'll be revealing later."
And that's it, almost. We sent Eidos a Q&A after the event, and you've just read many of their answers. However, they declined to answer quite a few of our questions. So we can't tell you whether Underworld will be longer than Legend, whether there will be episodic releases, why there's no PSP version or whether they're considering a Tomb Raider II remake.
Nor can we tell you why, oh why they made the T-Rex bit into a quick time event in Anniversary. (QTEs will be back in Underworld but "not as we knew them", according to Beacham. "It's going to be a new system. More flexible, more natural, a bit more freedom, more rewarding to the player.")
We can tell you this: what's been shown of Underworld so far is impressive and intriguing. It looks beautiful, it looks fresh, but it still looks like a Tomb Raider game. Crystal Dynamics appears to be focusing on why fans love the series as much as how to push it forwards, and that can only be a good thing.
There's still much more to be revealed, and it will be intriguing to see the new mythological environments Lara will get to explore. But so far, Tomb Raider: Underworld is looking spectacular. Much like Lara's tits.