As you creep, prompts allow you to reach for items on the shelves - a glass bottle, for instance, and a cereal box that starts to tumble as you brush past. Whether you can avoid creating the ruckus that attracts the thief's attention, I don't know - I didn't manage it in four attempts - but it's an interesting possibility. Shelby appears to be unarmed.
He's not a bad talker though, as he demonstrates when the robber confronts him and the speech prompts start swirling again, this time bobbing up and down in nervous agitation. Shelby can reason with the robber, and eventually get into an altercation and subdue him with a few well-timed button responses. He can even goad him into taking a shot by refusing to put his hands up.
The camerawork here - as with the other demos - utilises split-screen techniques and builds suspense by refusing to answer urgent questions until it's ready: the bullet grazes Shelby's shoulder, but you won't be shown this until the robber has panicked and fled the store, leaving you to suspect you've failed. Quantic Dream's David Cage has previously said that there will be no "game over" in Heavy Rain, but it takes some believing, and we still wouldn't put it past him to let one of the playable characters die in a situation like this.
Whether Shelby takes the robber out or takes a bullet from him, the scene concludes with the shop owner thanking him and sharing a detail about the Origami Killer. As with the earlier conversation that sent Shelby to the back of the store, there's one way for this to end, and by replaying the scene you expose the heavy hand of the machinery driving you there. Then again, you would be unlikely to replay the scene this way in normal gameplay, and it stresses the ease with which the developer suggests deviation without actually having to offer it. Other scenes will certainly allow for fuller deviation - this one happens not to, but you wouldn't know it. It's rather elegant, and being able to identify the seams by going over a scene a few times actually enhances your appreciation of how effortlessly they're concealed.
If you get a chance to try the demo more than once at the Expo this week, then, it's well worth doing so. Sony may be just as excited about shooting monsters in the face in post-apocalyptic American cities as the next publisher, but it's hard not to admire the company's faith in developers like Quantic Dream when you witness their work first-hand. As Sony's Shuhei Yoshida pointed out when we raised the subject of Heavy Rain's commercial prospects a few months ago, "sometimes the most creative products give the biggest financial success". Whether or not it turns out to be the case for Quantic Dream's latest, that enduring optimism is a feather in the PlayStation's cap.
Heavy Rain is due out exclusively for PlayStation 3 in 2010.