A little further searching on Youtube reveals that Episode 2 of Jesus: The Evidence is also available, though with an incorrect aspect ratio. This is the one I previously mentioned, featuring Morton Smith discussing Secret Mark. Smith first appears at the beginning of the 34th minute here, outside the Mar Saba monastery, so my earlier memory of the appearance turns out to be correct, and now one can see the whole context of the appearance:
There are other things of interest in this episode including more Geza Vermes and also Anthony Harvey. Ignore the "3 of 6" on the uploader's heading; this is episode 2, and the first few minutes of the episode are in a separate upload, headed 2 of 6. The character you see in the still above is Ian Wilson, the author of books on the Turin Shroud, who also authored the book Jesus: The Evidence that accompanied this series.