Per 
Item #: SCP-XXXX
Object Class: Safe Euclid
Special Containment Procedures: SCP-XXXX is to be kept in a 30cm2 lead box, which should remain well locked at all times, except during testing procedures. The box is to be located in sector 316-XC of the facility in a standard SCP locker. After incident 406C-XXXX-A, the containment is to be relocated to an off-site location, currently in [REDACTED], Alaska. At least twenty D-class personnel with thorough background checks and physiological analysis should be kept on-site at all times. The head of research, Dr. ███████ and Psychologist ██████████ should remain on-site at all times, and be treated as Class A personnel in the event of a containment breach or test causality. A helicopter pad is located north-east from the observation chamber and should be easily accessible in the event of a breach.
SCP-XXXX
After incident 406C-XXXX-A, the testing facility should remain separate from the observation facility, with an air-sealed lock separating them at the far-end of each building. In the event of any effects of SCP-XXXX carrying into the observation chamber, a full evacuation is to take place until the incident has run its course. Any personnel under the effects of SCP-XXXX or the pursuit of SCP-XXXX-A are to remain in the facility and be escorted back into the testing area if possible.
Any interaction or transportation of SCP-XXXX should be done with proper ear protection to avoid possible activation of SCP-XXXX. Any activity, testing, transportation, or other endeavors should be cleared by ███████ █████████, and done under the direction of Head Commander MTF Delta-9 ████████. Any interaction with SCP-XXXX that is not under the intent of triggering SCP-XXXX's effects should be done under the instruction of the current head of research endeavors with the use of earplugs with an NNR rating of 32 or higher.
No attempt should be made at opening or defacing SCP-XXXX, as this may result in an event similar to incident 406A-XXXX, as any attempt of opening or otherwise disturbing SCP-XXXX could lead to spontaneous transferration.
Description: SCP-XXXX is a Matty Mattel Music box that constantly plays the first six bars of the 1825 nursery rhyme "Pop Goes The Weasel"1. The rhythm will finish and is followed by a series of whirring and clicking noises, be for the rhythm repeats. It is discouraged that any personnel are to listen to the song, as it serves as the activation of SCP-XXXX, as well as being the cause of SCP-XXXX-A's eventual conjuration.
The box was first discovered in an abandoned apartment complex in the outskirts of [REDACTED], Montana after a murder investigation lead to the death of three police officers. The box was retrieved ██/██/1979, and propper amnestics were deployed to the local police force. The framing of ██████ ████████ was used as a coverup story to avoid suspicion.
Currently, the contents or inner workings of SCP-XXXX are unknown. Only one attempt of opening SCP-XXXX, which lead to incident 406A-XXXX. Any experimentation on SCP-XXXX is to be mainly behavior testing, rather than physical testing. Any disobedience of this directive will lead to immediate demotion to D-class personnel.
When a humanoid entity2 listens to the full song produced by SCP-XXXX, they will begin to hear a faint, slow repetition of the melody. This melody can only be heard by subjects under SCP-XXXX's primary effect, but it is currently unclear whether to sound is always audible, or whether it only begins when a subject listens to SCP-XXXX's song.
Eventually, after a subject has listened to SCP-XXXX, the conjuration of SCP-XXXX-A will occur.
An Crude Illustration of SCP-XXXX-A Done By D-class personnel ████████ ████████████
SCP-XXXX-A: SCP-XXXX-A is a humanoid entity that conjures when SCP-XXXX's song is listened to. SCP-XXXX-A is described as a tall, lengthy humanoid with a well-tailored vest and undershirt. It has exaggerated features, including elongated arms and fingers, as well as an abnormally large head. The entity lacks a face and has a large, non-organic box protruding from its face, as well as a small speaker protruding from its neck. Upon SCP-XXXX-A's vest is a pinned on name tag, with the word "𝐏𝐨𝐩." crudely hand-written across it with a black permanent marker.
SCP-XXXX-A has no recorded height, and no recorded weight due to its anomalous ability's. All current records of SCP-XXXX-A have proven undetectable via camera or video footage. Furthermore, any person not under the effects of SCP-XXXX is unable to perceive SCP-XXXX-A and is unable to interact with it in any way. It is currently unknown if the entity can interact with personnel not under the effects of SCP-XXXX.
After hearing SCP-XXXX, a series of events has been reported by test subjects to take place, varying from case to case depending on the subject. The general series of events are executed in the following format:
- Subject hears the melody of SCP-XXXX
- Subject immediately begins to hear a quiet, slow whistling of the song, still excluding the last two bars
- After 2-3 days, the whistling will start to grow louder and sharper, coming from all directions
- 4-5 days after originally listening to SCP-XXXX's song, the song will slowly localize, until it eventually sounds from outside of the room the subject is currently in
- SCP-XXXX-A neutralizes the target, generally using means pertaining to their greatest fear if possible within the given circumstances.
- SCP-XXXX-A can be heard whistling the last two bars of SCP-XXXX's song.
Any subjects that attempt to escape from SCP-XXXX-A find the entity to be fast and persistent, although some have described the entity to have a limping gait. All recorded terminations have been swift and skillful, no matter the current physical condition of the subject in pursuit. SCP-XXXX-A has shone the ability to alter objects within its vicinity in order to execute the target, including turning off or shorting electrical equipment and unlocking doors.
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