sentences:  These story elements are similar to the story arc of the Silurians, intelligent reptiles that lived on Earth millions of years ago, dwell underground and wish to one day return to the surface.Written by Roger Dixon, this six-part story was submitted on 16 January 1967.The story involved the TARDIS crew arriving on an Earth of the far future where a community of youth depend on the unseen Elders who dwell in the mountains.