When you enter the administration, you will overhear a conversation between Swan and Betruger, an argument on whether or not the situation is out of control.
Lobby and hallway
After the scene, the power cuts, and you are attacked from the left by a Z-Sec from the door. There is also a civilian zombie sitting next to the door, who will awaken when you approach. Behind this door is an Imp.
On the right hand size of the corridor is an office containing a zombie, as well as a weapon locker (combination 586) containing grenades.
Continue to the end of the corridor and speak with Webb, who will tell you to take the shotgun and to continue without him. The return trip to the lobby will have an Imp waiting in a corner. When you reach the lobby, two imps will break down a side door, allowing you to pass.
Go through the new door. The power gets cut as you go through the hall, with two imps attacking from the ceiling.
Through the next door, you will be attacked in series by two machine gunner Z-secs, and imp, and a pistol Z-sec.
Continue to the Data library. Enter the side door, and use the terminal to unlock the door. This starts a cutscene where the pinky demon will attack, first by damaging the door, then bursting through the window. Take him out quickly or run past him.
Enter the now unlocked door, where an imp stands behind, followed by a nother pinky, a Pistol Z-sec, and an imp. There is alos a zombie located in another closet.
Within the north hallway, you can find a Martian Buddy locker (code 0508) with a chaingun.
Contiune to the upper path back to the data library to reach the executive offices. Sargent Kelly will inform you that there is a growth infesting the complex,
After the first door, a montser closet will release an imp from behind. After this closet is a bridge where you overhear Kelly and another person trying to connect to the main network.
Past the bridge is a pistol Z-sec (approaching fro the left), and a zombie (approaching from the right). After dealing with both of them, head to the end, grab the PDA from the person on the right; this will allow you to exit the level, but will summon a large number of imps that attack scattered throughout the local room. It also unlocks a quick path back to the lobby.
With this new PDA, head towards Alpha labs again. When you reach the first door, an imp will teleport in at point blank, with another imp appearing behind you.
Entering the corridor will cause the power to be cut. Hide behind the boxes in the corridor, and attack the Machinegun Z-sec, then shotgun Z-sec. An imp will teleport behind the corner, and when killed, one inside the office.
Enter the office, and take the right-hand door to enter the network room. Collect the PDA for Paul Simons on the left, and watch for another Imp attack from the door.
Now, you can proceed to the exit, where you first met Webb.