Synopsis by Hal Erickson
In the second episode of the four-part story "The Space Museum," the Doctor (William Hartnell) and his companions must travel back in time to prevent a horrible fate from befalling them. Their first obstacle is to elude capture by the Moroks and their slave warriors, the Xeron. Rendering himself and his friends invisible, the Doctor passes through the Fourth Dimension -- and into the gaping jaws of terror. Written by Glyn Jones, "The Dimensions of Time" first aired on May 1, 1965.