When you start, if you turn around, you can see the teleporter you just used just dozens of feet away. Go through the only door to the observation access. The south door is sealed. Pick up the med kit in front of the door and follow the hall till you get to the teleport observation room. From around the corner a flaming zombie will run towards you. Pick up the shells on the ground and go go into the next room. The access card for that locked door is in this room on a chair. In the next chair is corpse....or so you think. It gets up and attacks you when you pick up the access card. When you exit the room two imps will attack you. Go to the area from which they came to get some goodies. Now go back to the southern locked door and open it with the card you got.

When you open the door two commando zombies will attack you. One has a chain gun. Go to a panel in the northern part of the room and use it to unlock the door in the door that says Storage 2. When you enter kill the zombie then pick up the armour and use the health station. Go through the northern door into the maintenance corridor. Go down the the corridor until you hear Betruger laugh. That will trigger a commando zombie and a fat zombie to attack you. After you kill them walk further and another imp will spawn behind you. Where the fat zombie was hiding pick up the PDA and use the code, 259, on the cabinet. Now go through the northern door. Kill the commando zombie in the middle of the room. There is another one higher up. The computers to the left have and imp and a zombie hiding behind them. Get the med kit and clip in the north-eastern corner and the security armour in the southwest corner. Next continue down the hallway.

In this next area an arch-vile appears. They summon four imps and then just leave (normaly) if you kill them quickly they can't summon anything at all. But don't get to close because they have a VERY strong fire attack. Get the med kit and adrenaline in the kitchen then proceed through the next door into the research corridor. An imp will jump towards you; after you kill it go to where it came from to get some supplies. Go through the southern door. On the other side is a commando zombie and a chain gun zombie further into the room so watch out. Look on the ground near the second zombie for some armour. Get on the nearby lift and ride it up. When you hear another arch-vile will spawn below the balcony your on. Crawl into the vent. Turn right to get armour then go back and go left. You will drop into a lab where Dr. Michaels is dissecting an imp.....cool. He tells you the code for the cabinet in the next room is 624. Next jump over the barrels and stuff to get to the research control.

As you go in the door you see an imp walking in the opposite direction. When you go in an arch-vile will appear spawning imps. Once he is dead or gone two commando zombies attack you. Pick up the med kits under one table and go through the northwest door. In the eastern part of this room there is a commando zombie waiting for you. Go through the northwest door to find it locked and then you get a new mission. So now go through the northeast door. But to the right of this door is a control panel that open a hatch. Crawl into the hatch and you will hear "Help me" kill the imp at the end of it and you will see the person it killed. Pick up his PDA. It tells you the code for locker #213. Now back to the door. Go through it and you will notice that there is not much light in there. To help a bit go to the panel and activate it to make a specimen tube thing go across the chamber. Follow it and you will be able to se much better. Kill the imps that you see along the way but make sure you keep following the specimen tube.

When at the end walk up the stairs and go through the western door. Type in the code 371 in the nearby cabinet and also use the nearby health station if needed. Next go through the western door. Turn left at the entrance and blast the imp. When the stasis tube come by start following it again till the end killing anything in sight. Then go through the eastern door to the lift access. Two imps or in this room so take them out with your shotgun. Pick up the plasma cells and the video and ride the elevator to the second floor. Walk to the left out of the elevator until an opening in the wall occurs. An imp comes out of it. Go through the next door to analysis control. When you go in you can watch a video about the soulcube. If you touch the panel near the door it will tell you that the soulcube is missing. Walk to the other computer work area and pick up the PDA. It has some e-mails on it that you might want to read. Pick up the nearby armour and use the health station. You will see a cabinet with a sticky note on the panel with the code written on it. If you type in the code an imp will pop out of the cabinet so be ready with your shotgun. Get the armour in there and then proceed through the next door. Kill the imp that crawls over the railing and the two commando zombies at the end of the corridor. continue through the door into central processing.

Move into the west and kill the two commando zombies there. Also an imp come from the eastern part of the room. Go to an office where you'll find a PDA telling you the code for the secure storage room, 725. Go type it in and go into the room. Use the code 0508 on the Martian Buddy cabinet. Now go to the other locked door and type in 463. Go through the door and kill the arch-vile and what it summons. Enter the elevator and ride it to Delta Labs Sector 3.