Body Thetan

In Scientology, a thetan is the term corresponding to one's "spirit", and a Body Thetan is another thetan (spirit) who is 'stuck' in, on or near a human "meat body" because of an incident caused by an ancient galactic dictator named Xenu. All human bodies were said by L. Ron Hubbard to be covered in clusters of these misplaced thetans.

This information was originally published openly by Hubbard and the Church of Scientology in a number of "policy bulletins" (HCOBs) and "policy letters" (HCOPLs), but were later made secret. It was also alluded to (although not described in any detail) in a publicly available cassette tape Hubbard released called "Ron's Journal 67", addressed to "all staff and students of Scientology organizations". For some years, it was reported by former Scientologists that the material was still being used, but not divulged until one reaches the third Operating Thetan level (or OT III).

According to many former Scientologists who have reached Operating Thetan levels, Xenu/Body Thetan material is still being taught in higher levels on Scientology's Bridge to Total Freedom.