Just to get the ball rolling for you, the game play picks up right after the initial trailer that was shown at TGS. Detective Sebastian Castellanos was just ambushed by a mysterious hooded figure and knocked out. He awakes in the predicament that this below clip starts off with and the fun and excitement continues.

This is the official game play video released by Bethesda and while it seems that there are a few weird edits that occur I can attest that the scenes missing are really just filler "walk to point B" kind of things. They do give you an extended feel for the environment but do you really need to see the main character walking for 30 seconds here or a minute there? Not really. Also, the cut to the cabin and tunnels is almost exactly how it happened in my second half of the demo so I am pretty sure that is part of the game play.

So sit back, turn your volume way up, turn off the lights, and have a fun watch. Now if only we had more than just a release year to work off of to get even more excited for The Evil Within.