Darkling (Star Trek: Voyager)

Plot

The Doctor attempts to improve his program by including elements of the personalities of various famous people that he admires, taken from holocharacters of them. However, the darker, less well-known sides of these people's personalities form a second, evil personality. This evil version of the Doctor attempts to murder an alien from the planet being visited by Voyager by pushing him off a cliff. The evil twin also temporarily paralyzes Lt. Torres when she discovers it. It later jumps off a cliff with Kes but is beamed back to Voyager while falling. At the end of the episode, the Doctor's program is restored to normal. As the episode concludes, the Doctor is heard reciting part of the Hippocratic Oath.