Photograph taken during initial investigation.
Item #: SCP-XX
Object Class: Euclid
Special Containment Procedures: Hallway 184-E has been sealed to prevent entry.
Description: SCP-XX refers to a persistent electrical buzzing noise emanating throughout Site-23. It is only perceivable by human subjects.
Containment teams have triangulated its location as near a storage closet within Wing-G. This closet contains no materials other than wooden pallets, and is notable for containing a carpeted floor. Its position aside an air conditioning vent leads to nearby individuals reporting chills.
Discovery: On 2019/07/12, Site-23 Director L. Halford went missing. Surveillance footage identified them as having been last seen passing the closet, exclaiming that they heard SCP-XX coming from within, and entering. The door was still ajar when security forces arrived on location, but Halford was not found.
Seventeen days later, Director Halford was found lying in the fetal position within the closet.
He was removed to a nearby medical bay and examined. Analysis found he exhibited signs of UV radiation exposure and minor iodine deficiency. Blood tests identified residual amounts of an unknown substance, which exhibited a sedative-like effect on human tissue. Halford's embedded subdermal tracker1 was inoperable and was replaced. His psychological results were similar to profiles of solitary confinement.
Upon regaining consciousness, Halford began complaining of stinging pain behind his right eye. Close examination revealed an optical sliver made of an apparently metallic material. Sensors show that it continuously emits medium-frequency radio waves. Further analysis has been unfruitful.
Addendum XX-1: Possible Prior Incident
Following the publication of this file, security officer J. León reported having also been trapped within the closet. They had been missing for nine days, which had previously been unrecorded.
In an interview, León described the interior:
It was just totally dark. Even after my eyes adjusted, I still couldn't see my hands or legs. And it was enclosed, but large, way bigger than the closet should be. Definitely a different space.
Oh, right, the eyes. At first there were many, but then later just two, or three. Staring at me. They don't blink. After a couple days, I tried to get closer, scare them away maybe, but I couldn't. They just kept watching. I don't know what they are, but I got this feeling that I had something they wanted.
Sometimes when I got hungry, things would get even darker, somehow. Completely pitch black. Only thing I could see were more eyes, getting closer. Every time I wanted to run away, but I couldn't. Like I was tangled in invisible thorns, bleeding, without the blood. After an hour it would go away. I got some sleep and felt better.
It was terrifying, just like the others said. I should've stayed away, but I couldn't. I've felt something missing ever since.
A subsequent sweep of Hallway 184-E failed to identify any anomalies other than SCP-XX. The veracity of León's statement is disputed.
Addendum XX-2: Site-23 Inventory Incident
Beginning on 2019/11/07, Site-23 began its quadrennial facility inventory. As required, all facility personnel were given medical examinations.
While most subjects did not report any pain, it was found that 98% of facility staff had identical optical slivers within their eyes.