Take cover on the side of the lockers facing the wall. The best way to obtain it is to enter the first floor using some disguise and then moving to the area in the back past the reception with the blue lockers, to which the manager will come to smoke. The building manager's uniform comes in very handy since the head of security is expecting him. The Manager Related Challenge: You Can Manage It is done by simply killing or subduing the head of security and then dragging her body to the retinal scanner to unlock the elevator. And this method is not recommended to players playing on higher difficulty. The problem with this method is that it is almost impossible to do it without starting a shootout. The Head of Security Related Challenge: I Got My Eyes on You However, if a move to infiltrate the elevator is not made short after, one of the guards that patrols near the retinal scanner will realize that it has been deactivated, subsequently causing him to head into the security office and reactivate it. The computer is close to a door, so all you really have to do is sneak inside while they are turned away and use it. You can subdue and/or kill them, but it's actually easier not to since it will cause some noise. The most direct way of disabling the elevator door is to simply hack the retinal scanner from the security guards' office. Hacking the Lock Related Challenge: Hack'n'Backslash Note that the laundry tunnel (in the far-end of the laundry room) seem to have unlimited amount of space for you to get rid of the bodies, dispose 3 in a row undetected and you will get "Laundry Day" challenge unlocked. It can be unlocked in three different ways. The goal is the elevator near the reception desk, which is locked with a retinal scanner that only allows the head of security, a bossy woman in a suit who patrols the first floor, to call for the elevator. If you're using disguises, the custodian disguise is among the most useful in the lobby since there are almost no other ones on the first floor and it allows access almost anywhere. From here, if you have the suit, you can try to enter the back part of the first floor, though it's almost impossible to do it without getting spotted since there are a lot of guards and almost no cover in the lobby. :) Throw something to distract them and then go up the stairs. Wait for them to finish, at which point they will enter a nearby room with some shelves. A group of NPCs, including guards and custodians, will be talking on the other side of the glass window. If you enter the building, there is a room with a ventilation shaft that goes over the guard office in the tunnel and into the Blackwater building basement. On the far side, there is a big water pump that can be disabled to lure a custodian out. The park, along with a large parking lot, is located along the path to the right of the lobby entrance and has a fairly small guard presence. The lobby will be guarded by armed security guards who won't let any non-staff members through. The park and the connecting staff building can be used as an entry point into the lobby to get past the guards watching the entrance. The first segment covers the outside park, the staff building, and the basement and first floor of the building.