Star Trek celebrity guest Joan Collins playing Edith Keeler in an appearance on the original series in City on the Edge of Forever episode.
The top picture is the actor in normal circumstances, and the bottom picture(s) is of the actor in their specific role(s).
6 Pictures from City on the Edge of Forever
Most famous for her role as Alexis Morell Carrington Colby Dexter Rowan in Dynasty the TV Series. She also starred in classics like Empire of the Ants in 1977, and almost 80 other movies, plus many TV guest appearances, since.
The City on the Edge of Forever -Star Trek: The Original Series - 6 (episode # 1.28) -Playing Edith Keeler -A social worker who lived during the first part of the 20th century was rescued at a car accident by Dr. McCoy after escaping into Earth's past. Kirk falls in love with her, but to reinstate the timeline, she has to die.