When the chapter begins players will be teamed up with Joseph, and it looks like the objective is to check on the well being of Kidman a few floors below. Before you get too carried away, spend a bit of time picking up loot, including the Journal of Sebastian Castellanos - September 1, 2012. You can also take a trip back to see Nurse Tatiana if you need to save and perform some upgrades.
Make your way through the rubble and down through a hole in the floor. When you spot an acid trap, spend a moment dismantling it, then move along the hallway until you trigger a cut scene.
Tip: This chapter is most easily completed by using stealth. Spend some time disabling traps and sneak killing your enemies. The Last thing you want is to be running through the hallways tripping over bear traps.
When the cut scene is finished you'll need to approach the elevator and shoot the cable that's holding it up. It's here that you'll find yourself split up from Joseph, so make your way through the vents, emerging to get another look at The Keeper.
He's gone for now, so make your way through the hall, disabling any traps you encounter along the way. When you spot a couple of enemies up ahead, take a moment to time their movements, then approach them and go for the sneak kill. Just continue to repeat this process, dismantling traps and using stealth to bypass your foes.
Disable one last acid trap before you find yourself descending a stairwell. You'll emerge in another hallway, but it's just more sneaking and disabling mixed with a touch of looting for good measure. When you spot The Keeper, allow him to finish his work before moving on and dismantling the bear and acid traps that he's laid.
Tip: Players will find quite a bit of Green Gel laying around this next part. Make sure to duck into side rooms, smash boxes and grab up all that you can.
With the traps out of the way, continue a few feet ahead and duck into a vent on the right. It'll bring you to yet another hallway, this time leading outside. Make your way around the rubble and down several floors to a silver case that contains some Super Mag ammunition. When you make your way back into another hallway, you'll have a door in front of you and another on the left. The one in front of you will take you to see Nurse Tatiana, and the one to the left will allow you to progress further on.
Continue making your way forward, dropping through another hole in the floor and into a hallway. There will be a creature at the far end with some lights on him. Maintain your distance and kill this guy from range. He seems to have motion sensors on his body and will explode if you get too close. You'll also have another one of these creeps sneaking up behind you from one of the side rooms. Watch your back.
Jump into another vent and continue moving in the only direction available. You'll emerge in what appears to be the stock room of a kitchen. Spend a few moments looting up, then move through to the next room. You'll get a brief cut scene that shows Ruvik, The Keeper and Joseph, and when it ends you'll want to watch your toes.
Once the little vacuum cleaner blades of death start zipping around the room and trying to cut your feet off, disable any bear traps that are in your way and head for the door that Ruvik was previously standing in. There's another acid trap there, so do your best to disable it and move into the nearby hallway. This should put those annoying little devices behind you once and for all.
The problem is not what's behind you, unfortunately, but rather what's in front of you, and that's The Keeper. You'll be inside of a meat locker with this jerk, and the best you can do is avoid him and stay alive. Your ultimate goal is to jump into the same vent as Joseph did, and in this case Freeze Bolts might be your best bet. They will allow you to completely halt The Keeper's progress, buying you precious seconds to heal up or put some distance between the two of you.
It's all smooth sailing after making your way into the vent, so just move through the hallways and grab any loot laying around. When you finally make your way outside you'll spot Leslie and Kidman, triggering the chapter ending cut scene.
Continue with The Evil Within - Chapter 14 - Ulterior Motives.