I’ve rewatched “That Which Survives” (Star Trek: The Original Series, season 3, episode 17). And it’s about a strange lady coming on Enterprise and killing a redshirt. Then, when Kirk, McCoy, Sulu and one of science stuff beamed down on a “ghost planet” the Enterprise was “moved away from it” on a very long distance. (Spoilers!) The lady continued to appear now and then on the ship and on the planet killing another redshirt and the science stuff (on the planet). Then she tried to kill Sulu and then Kirk, and made with ship something that it was accelerating and going to blow up. Of course, Scotty and Spock dealt with in the last second before the explosion (and yes, they were on warp 14 and didn’t turn into lizards, it's strange isn’t it?). On the planet, the Captain has found out a cage with a computer producing the copies of the lady and sending them to kill people to defend a base. Well, then Enterprise came back, Spock beamed down and destroyed the computer. So, everybody’s saved.