As part of the story, you will head to Lussuoso Hotel to try and locate someone. Of course, it isn't that simple, and you get locked in the restaurant area, with two doors that can be opened somehow.
To unlock these doors, you must do the same thing as you did to open the big door in the laboratory. You must locate four power switches and hack them online to unlock the doors to the Lounge and Disco areas.
Switch one is located near the Disco door. To the left of this door is a set of stairs, then just after to the right is an entrance to a smaller room. Inside this room, on the back wall, is the fourth switch.
The second switch is located exactly opposite the entrance you came in to reach the restaurant area. Eventually, if you follow the right wall, you'll come across a storage room and the switch in the corner on your right.
Switch three can only be accessed through a vent in the room you found switch two. Crawl through and on the back wall is the hackable switch.
These three switches open up the Lounge door. Going through this door will lead you upstairs to another shootout. Eliminate all enemies, then proceed the linear path to the room at the very end. Inside this room, on a pillar in the center, is the fourth hacking power supply.
With the final switch activated, the Disco is now open to progress with the rest of the mission.
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