Fallout 4 created by Bethesda Game Studios.
Images used for educational purposes only.

- The Cambridge Polymer Labs are located in central Commonwealth territory, just north of the bridge that leads down to Diamond City and across the street from the C.I.T. Ruins. You’ll wind up coming here as part of the Underground Undercover quest on behalf of the Railroad, though you may also discover the location if you happen across an Eyebot that’s running advertisements for the Labs. They appear more or less randomly while you travel.

- The area surrounding the Labs is pretty dull, and the exterior of the Labs equally so, so you might as well just pop into the front entrance upon arrival. Here you’ll be greeted by Molly, a Mr. (Mrs.?) Handy robot who will ask you to ‘apply’ for a position. After you’re given a position Molly will invite you on an orientation session; feel free to follow her if you want a history lesson. You don’t have to apply to wander around, as Molly doesn’t seem to care if you wander into the building on your own. You do have to listen if you want to trigger a quest, and you’ll get different items depending on the results of your application.

- Before following Molly you can have a quick look around the first few rooms of the Labs. Through the door on the right from the entrance is a kitchen; inside you’ll find a Nuka Cola Quantum inside a Nuka Cola Machine. A door here leads to a few locker rooms, as well as the clean room where you’ll begin the next quest. To the left of the entrance is the orientation room, where you can watch a presentation on the Labs, and a few bathrooms; aside from some Stimpaks in one of the bathrooms there’s little of interest. Behind the front desk and on a counter is a Vault-Tec Lunchbox. Last up are some stairs, also behind the front desk, though they lead to offices with little of interest… 

- … aside, that is, from a Master locked door. If you’re skillful enough to do this you’ll find the Director’s room. You can also get in here by destroying Molly, as she carries the CPL Director’s Key. Inside is the Director’s Feral Ghoul, easily dispatched. Check the terminal for more info on the place, and look beside it for a Massachusetts Surgical Journal.

- The quest Cambridge Polymer Labs is triggered if you enter the clean room. There are two ways to get inside: either follow Molly during the orientation process and she’ll open it for you, or find the room yourself and use the terminal outside the clean room to open it up. Either way, the door seals behind you, and you’ll need to walk through the remainder of the Labs to escape again. A hole in the wall will allow you to easily wander out.

- The clean room leads to an open lab area. A terminal on the central table (Ericka’s Terminal) explains what happened here. Look to the larger computer bank to the right and you’ll find Unidentified Sample 11317 sitting on the computer. This computer - a Polymer Coating Applicator - can be used to create an item, but you need some more stuff first.

- A door to your left leads into an open, two-floor area. Multiple Feral Ghouls are inside, though they won’t become active until you get too close to one. They’ll drop down from upper floors, so be ready for ambushes. Back up into the previous room will help you deal with death from above attacks. Check the rooms on the lower level for Unidentified Samples 3111, 413, and 65, along with lots of other junk. In particular, look for a Hazmat Suit on one of the shelves.

- The upper floor has a few more offices with more Ghouls and lots of junk to steal, including some more useful items in an Expert locked safe (not far from the stairs). You can use the terminal beside the safe to open it as well. There’s an Expert locked door up here, across a crumbled walkway, and inside you’ll find a Tesla Arc trap, a mine on the floor, another Ghoul, a Radioactive Containment Password Holotape, and, beside a terminal, Unidentified Sample 611. The terminal itself can be used to activate the Turrets in the main room, also bringing Molly out to try and kill you. This will open the clean room door and complete the quest. (You can also use this terminal to get Bergman’s Password, part of the Underground Undercover quest mentioned above.) The offices across from this locked room contain Unidentified Sample 49, and… not much else.

- In the third room on the ground floor (accessible by walking through the wall in the second room - watch out for more Ghouls inside) is a terminal. Hack into it and you’ll open up an isotope containment chamber nearby. Doing so will awaken a Glowing One in the pool, and if you try to enter (through the last door on the ground floor) you’ll have to fight it off. Beware the heaps of radioactive barrels in the room. Check the shelf on the other side of the water for U-238.

- Now you need to find a way out, assuming you didn’t open the clean room by making Molly all evil and such. Reenter the room with the Polymer Coating Applicator, and insert Samples 3111 and Sample 611, along with the U-238, into the Applicator’s three nodules. Run fabrication with these three items in place to create a Piezonucleic Power Armor Chest. Pick up the Chest to open the clean room and complete the quest.