The Top 25 People Crippling Scientology, No. 20: Trey Parker and Matt Stone - 2011-08-17
And as you can see from that screenshot, the title that Parker and Stone put up throughout the Xenu segment -- "THIS IS WHAT SCIENTOLOGISTS ACTUALLY BELIEVE" -- really shifts this episode from farce to political satire. This IS what high-level Scientologists are asked to accept, after several years of membership and several hundred thousand dollars in fees: that disembodied, indoctrinated alien souls are attached to us after they were brought here 75 million years ago by a galactic overlord named Xenu, and only Hubbard's techniques of "auditing" can remove them from you so that your superhuman potential can be unleashed.
There's something about putting the OT III story in a cartoon that makes it even more stark-raving mad than simple words can convey.