The first task facing you once you make it to the office complex is simply getting down the hallway. About halfway down the hall there's a live wire, randomly discharging electricity into the puddle on the floor. And the door that you can reach is locked. Luckily, there's a ventilation duct just before the live wire. Crawl over to the duct and break the grate with the Crowbar. Be careful, because the discharge can still hit you if you move too far to the right of the grate. Crawl into the duct and follow it to the end. Break the grate and climb into the room. Beware of the Barnacle, and be aware that more will be bursting through the ceiling while you're in the room.

In the corner, you'll see a door with a sign reading "high voltage." Open it, go in, and flip the switch. Now the hallway is safe.

At the other end of the hallway, you'll need to break the window and climb through. The water-filled room to the right has its own electrical problem, but you'll deal with that in a moment. For now, it's time to get some supplies. Go to the left and into the little alcove with the wooden door. A Zombie will begin bursting through the door. Wait until it has cleared a passage, and then kill it. Go in and get the pistol clips. Go out and continue to the left until you come to some crates. Break them up, and continue on.

You'll see a supply room with a locked gate. A security guard will be standing there, with a Zombie sneaking up behind. Kill the monster, and the guard will open the door to the supply room, wherein you get the Assault Shotgun. You can also find some health and HEV power if you climb down the ladder in the area just before the supply room.

	Getting to the switch on the far wall will require some careful jumping.

Now go back to the room filled with water. Jump up into the window, and then onto the table. You need to jump first to the sink, then to the table on the far wall (which is next to a health dispenser), and finally to the counter on the other side. Flip the switch to turn off the light. Turn on the flashlight, and drop down into the water. The closet near the sink has some HEV power in it. Now open the grate on the wall with the Crowbar and climb in. You'll have to deal with some Headcrabs, and make sure you duck under the fan. When you get to the end, break the grate, but don't jump in the room just yet.