East Wing, Basement & First Boss

Take the Diamond Key down through the fire hallway into the East Office. Clear the zombies, then open the small locked office's safe using the combination from the Police Memorandum (2236) for Acid Grenades and the R.P.D. Map. There's also Green Herbs behind the desk and Ink Ribbon on another desk.

Past the double doors and down the hall, use the Diamond Key on the first door but hold off entering — grab the Red Herb further down first, then take the second door into the observation room. The third door (locked by a different key) is the interrogation room: grab the Cable and the Eagle Stone quickly, since a Licker crashes through the window shortly after. Use the Diamond Key back near the dark room to open the evidence room — clear the zombies and search the lockers for Film A, Bowgun ammo, and a locked locker (Lockpick) holding an Explosive.

Back in the west office, grab the Green Herb, Handgun ammo from a locker, and the Memo to Leon on a desk. In the small side office, the wounded Officer Branagh stands up as a zombie — kill him and take the Detonator from the desk, then combine it with the Explosive for a ready-to-use Explosive + Detonator.

Use the Explosive + Detonator on the wrecked helicopter debris blocking the door in the fire hallway, then head inside to the chief's office for a cutscene with Chief Brian Irons. Past his office, flip the light switch in a dark room to trigger a scene with a girl — Sherry Birkin — fleeing after hearing a scream. Grab the First Aid Spray in the chest and Secretary's Diary B on the table. Back in the chief's office, Irons has vanished — take the Heart Key and his desk chair diary. The painting behind his desk hides notches for three animal stones; you have two so far and still need the second half of the Blue Stone.

Take the Heart Key back to the East Office corridor and open the locked door on the left (consumed on use). Grab the two Green Herbs on the floor, then use the Cable on the electrical panel at the end — this seals the windows so zombies stop climbing through them (you can also use it on the panel where the first Licker appeared, for the same effect there). Head down the stairs; three zombie dogs are waiting in the basement.

In the first room down the right-hand basement hallway, grab the Green Herb and the Basement Map, then use the power control panel. It feeds the weapons vault's card reader, and needs the switches set without crossing 80 volts:

Done correctly, the vault's card reader light turns from red to green. The left basement hallway leads only to an underground parking area with a Green Herb — nothing else to do there yet.

Follow the left basement hallway to its last door, then a Red Herb and two zombie dogs in the outer passage before climbing down a manhole. In the small underground room ahead, save your gear and step back out to trigger a scene — Sherry slips away through a gap, and you take control of her.

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Climb the elevator up, avoid the two dogs outside, and find the water tank room (grab the map on the wall). Push the boxes into a bridge: push the right box all the way, climb the remaining boxes and drop into the small gap to push the center box right, then push the left box all the way too. Flood the tank at the control panel and cross to grab the Clover Key on the shelf. Ride the elevator back — Sherry tosses her items to Claire before running off on her own.

Back as Claire, collect what Sherry left and return to the basement hallway — two Lickers wait there now. Use the Clover Key on the morgue's double doors; grabbing the Red Keycard off a shelf wakes the corpses, so move fast. Use the Red Keycard on the weapons vault's reader (it turns from green to blue) to get in.

With the Clover Key, head to the rest room behind the main hall stairs (Ink Ribbon, Acid Grenades, and the Watchman's Diary). Then use the Clover Key and Lighter on the locked door at the end of the interrogation room hallway to enter the press room — kill the Licker inside, then light the boiler with the Lighter. The numbered busts on the wall need to be lit in this order:

A Golden Wheel drops from a painting when the sequence is right; grab it along with Film B on the table.

Take the Golden Wheel and the Crank Handle to the library upstairs. If you'd like, stop by the dark room first and develop any film rolls you've picked up. In the clock tower, use the Crank Handle in the wall notch to lower the stairs, climb them, fit the Golden Wheel into the gears, and press the button. A metal wall opens, revealing the second half of the Blue Stone — combine it with the first half for the complete Jaguar Stone.

Return to the chief's office with all three animal stones (Snake, Eagle, Jaguar) and place them in the painting's notches to open a hidden passage — you'll run into Sherry here again. Before taking the elevator down, stock up on your strongest weapons and healing items. Downstairs, a cutscene shows Chief Irons attacked and infected by a parasite — this is William Birkin's first mutation. Push forward into the taxidermy room, where Irons threatens Claire before dying, then grab the Acid Grenades and head down the metal stairs into the cavern.

Mutant G

Keep your distance and hit it with Explosive or Acid Grenades — the Sub-Machine Gun works well too if you picked it up earlier. Dodge the parasites it spits out; after enough hits, it dies.

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Regroup with Sherry, then head back through the cavern to the metal bar at the far end — press the button to lower and climb a new set of stairs.