Scientology: Galactic Emperor Xenu?

In this ABC video clip (uploaded in 2010), Scientology spokesman Tommy Davis is asked gentle questions about his faith by the interviewer, who wants to know if it's true that a Scientological article of faith is that the human race has its origins in the strange business of energy beings strapped to volcanoes by a space-tyrant and so forth. It's true that there's nothing objectively stranger about this than reincarnated saviours, plagues of boils, transubstantiation, or talking burning bushes, but Davis doesn't say this. Instead, he evinces this bizarre, put-upon reaction, insisting that this factual question is "offensive" and eventually storming off the set.