Alpha Labs - Sector 4: Union Aerospace Science Division

Alpha Labs - Sector 4: Union Aerospace Science Division is the eighth level of Doom 3. This sector seals and prepares shipments of processed hydrogen fuel for dropship distribution to UAC bases and subspace platforms. The system is fully automated and personnel access is limited due to open machinery hazards.

The player must navigate either the EFR or extend the service bridges. The EFR activates various moving platforms throughout the level, while the service bridges provide a quick but dark crossing. At the end of the level the Vagary (first boss) appears.

The level also includes the infamous "they took my baby" sequence.

Summary
In order to reach EnPro Plant the player must go through the final sector of Alpha Labs. In the beginning of the level the player finds a scientist trapped in a reactor chamber and is given the option to open the chamber or activate it. If they choose to open the chamber, the scientist opens the storage room full of supplies for the player. If the player chooses to activate the chamber, the scientist will be horribly murdered inside the chamber and the player will be rewarded with nothing but an enemy ambush. Proceeding through the sector, the player is informed by Sergeant Kelly that they'll have to make another choice: to get around the level the player must either use the EFR system or extend the service bridges. The first way requires the player to jump between multiple platforms and ride on conveyor platforms avoiding various machinery, but in this case the player won't meet a strong enemy resistance. If the player chooses to go the service bridge route, they won't have to do any platform jumping, but will have to fight more enemies along the way. In the end, the player reaches a large chamber covered entirely in web and organic matter where the player has to fight the game's first boss, Vagary. The same chamber has the exit to EnPro Plant.

PDAs

 * Michael Abrams. Found in Reactor Substation 1.
 * L. Kaczynski. Can be obtained by killing L. Kaczynski.
 * Henry Nelson. Found in EFR Staging.

Video disks

 * Mach-2 Chain Gun Briefing: Reactor substation 1

Characters

 * L. Kaczynski
 * Sergeant Kelly
 * Elliot Swann
 * Jack Campbell

Enemies
Note: since there are two paths the player can choose in this level, it's impossible to kill all enemies in one playthrough. This table includes only enemies that can be fought and killed.

Weapons/Items
There are also four health stations on the level, with 100 health in reserve each, although only three of them are accessible at any one playthrough.

Storage Cabinets

 * Storage Cabinet #064: 651. Contains: cells (large), clip (large), armor shards x3. This storage crate can be accessed only by using the service bridge route.

Secrets

 * There are two plasma guns hidden in this level, one for each path the player can take. If the player decides to use the EFR system, they can access the plasma gun at the very start of the conveyor sequence. The player has to jump on the platform right after it emerges, then quickly jump on the pipe above it, and the plasma gun and other supplies will be lying behind the pipe. However, if the player chooses to use service bridges, they can find one by finding a secret passage located in EFR Substation 3 room. In that room, there's an armor suit sitting near a wall that opens when getting close to it, opening the passage. A voice is heard saying "Over here". The plasma gun and other supplies are in a room at the end of this passage. One should be careful, as picking up the plasma gun here triggers an ambush.
 * In the room where the player needs to choose between raising the bridges or using EFR system, there a ladder that leads down to some supplies and an ambush. However, the player can jump over a nearby pipe and explore the rest of the area below, and eventually can find a lone armor suit sitting on the floor. Upon getting close it, it triggers a massive ambush, but upon fighting it, opens up a closet with even more supplies.
 * During the conveyor sequence (if the player chose to go using the EFR system), the player will need to get past a rotating device with long "arms" sticking out of it. The player can jump on it and get pushed by the "arms" behind said device to find some additional supplies. The player can return to the platform the same way.