Do you think that the Watchers exist or not?

The Watchers refer to the Grigori (which means "The Watchers"). The story of the Watchers first is told in the Book of Enoch--an apocryphal book that was but is no longer included in the Christian Old Testament. The Grigori are the fallen angels who brought culture and arts to mankind--which was considered to be a bad thing in the Book of Enoch because bringing culture, technology, and arts to mankind supposedly also brought vice and loss of innocence. It is mythology. Saying that they visited earth in space ships is just more mythology --but sillier than the original mythology.