(written from a Production point of view)
Mary Margaret Thompson is an actress who appeared in several episodes of Star Trek: The Next Generation. As a background actress she received no credit for her appearance and was identified by the call sheet of the episode "Descent", dated on Thursday 22 April 1993, and a makeup continuity polaroid of her. On the latter one she was named Mary Thomson. Her Starfleet uniform was later sold off on the web.