Per 
Special Containment Procedures
SCP-XXXX must be kept in an airlocked chamber which, for monitoring purposes, must have at least one window. The chamber must be kept below 278.15K (5°C) at all times.1
During the entity's resting state, the chamber must be kept sealed. During the entity's active state, the airlock must be released to allow airflow through the chamber.
SCP-XXXX is currently contained at Area-02. Its current containment chamber consists of a large, glass tank with liquid nitrogen pipes bordering the inside walls.
Description
SCP-XXXX in its resting state
SCP-XXXX, unofficially known as The Bodiless Child, is a gaseous entity that exhibits two states of existence. In its "resting" state, the entity appears as a cloud of pale-blue smoke that is unaffected by the pressure of its container. At lower temperatures, SCP-XXXX tends towards complete transparency, whilst at higher temperatures, it tends towards opaque, blueish-black smoke. When kept at its containment temperature of just below 278.15K (5°C), the entity is translucent with a through-visibility ratio2 of 54%. The entity tends to form the shape of a human child, but does not walk or communicate.
In its "active" state, SCP-XXXX appears to flicker between its appearance in its resting state and a human child. As of May 2020, there have been 478,611 recorded cases of missing children linked to SCP-XXXX since its capture in 19623, although there are at least 2,000 additional unconfirmed cases. The appearance of the entity in its active state matches that of the children that have gone missing. SCP-XXXX has exhibited the ability to do this with any child on Earth, regardless of proximity. Below the 278.15K (5°C) threshold, the entity is limited to being active once every 24 hours (on average)4. Above the threshold, the entity becomes highly active and has been observed to enter an active state 7-10 times faster, depending on the temperature.
The flickering tends to reduce and completely stop within 30 seconds - 2 minutes. Once the entity is stabilised, it is able to move freely using the body of the child and communicate using the child's voice. The child's pupils and irises will appear to be filled with pale-blue smoke. No other abnormalities are observed.
While the entity is in this state, it must be released from its containment chamber5 and supplied with all normal requirements for a human child to survive:
- air circulation,
- clean water,
- food and
- comfort
until it begins exhibiting any of the following behaviours:
- uncontrollable shivering,
- slow or slurred speech,
- a sudden drain of blood from the face,
- becoming unresponsive to verbal communication or
- the smoke in the eyes beginning to clear
at which point, it must be resealed inside its containment chamber. The child will usually lose consciousness within 10 - 30 mins. Shortly afterwards, the child will die and SCP-XXXX will exit the body through the mouth and nose. At this point, the body can no longer be occupied by the entity and must be disposed of appropriately during the next instance of the entity's active state.
Discovery
SCP-XXXX first became known to the Foundation in the year [DATA EXPUNGED]. A series of reports of children becoming "glassy-eyed" followed by their deaths was sent to the Foundation for investigation. Agent Troy Lament led MTF Mu-13 in Operation Nightsweep, the only mission to successfully capture SCP-XXXX. It was conducted on the 4th of January 1962 in [DATA EXPUNGED], Siberia.
Below is a transcript of the radio transmissions during the capture of SCP-XXXX.
Studies
Dr. J. Marley
All studies of SCP-XXXX have been led by Dr. J. Marley since its capture in 1962.
Marley's Theories
Dr. Marley has proposed multiple theories since beginning studying SCP-XXXX. Many have proven to be true. The list of as-yet-unproven theories are as follows:
- the entity is attempting to find a compatible body,
- the entity will always remain in its resting state at a low enough temperature,
- the entity is a bodiless soul and is able to remove the soul from other bodies.
