68%Strong matchZERO PROTOCOL
87%41187% positive reviews, Very Positive across 411 reviews·Survival Horror · Atmospheric
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You're a security officer deep within Area 51. Scan the staff, verify clearances, and decide who can enter the elevator and who absolutely mustn't leave. The deeper you go, the less certain you are that anyone standing before you is still human.
Security 51
Steam
Security 51 is an atmospheric horror security guard simulator inspired by Papers, Please, and SCP paranoia. You're on duty in the underground bunker of Area 51, where the most dangerous part begins at the elevator: the shaft descends for miles down to unknown levels. Whether it's laboratories, anomalies, inhumane experiments, or something alien—you're not supposed to know. Your task is simple: let in those who have access and stop those who don't... even if everything looks "right" on the surface.
Everyone who passes through your checkpoint carries papers, passes, or verbal orders. Your job is to check names, positions, clearance levels, and time, ensuring the number of people entering and leaving matches, and pay attention to any oddities. These could be incorrect answers, behavior that deviates from protocol, slurred speech, or even documents that seem too perfect. As time passes you'll catch yourself thinking that something's wrong more and more, and the only thing to rely on will be the protocols. But even they can be wrong.
With experience, you'll gain increasingly more accurate methods of identity verification, such as fingerprint verification or blood testing. Did that janitor simply open the wrong door, or are they a spy for an enemy government? Or are they not even human? When in doubt, quarantine the suspect. Sometimes you'll make mistakes and lock up an ordinary employee, and sometimes you'll find a titanium cell ripped open from the inside. Some decisions will have immediate consequences, others only after several shifts.
What should you do if the elevator coming up from the lower levels registers as empty on all the cameras, but when the doors open, a person is standing inside? Is this a camera system malfunction or something else? Or what if the employee who went home already rises from the depths with the same papers? The decision is yours.
Remember, it's not just about who you let in, but who or what you let out into the world.
Steam data © 2026 Valve Corporation. Trademarks are property of their respective owners.
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