The Enterprise is sent to pick up a scientist, Dr. Lee Chin, who has requested to return early from a research trip. Kirk and Spock beam down to find the planet inhospitable and, apparently, trying to kill them. It seems that Dr. Chin has disturbed some sacred place by removing artifacts from it, and brought down a curse upon them. Spock is fatally injured, but Kirk sustains him by sharing strength through a very risky mind meld. And, happily, they find it written on a stone tablet that to end the danger there must be "an act of pure, unselfish love". Obviously this was nonsense and there was some scientific explanation for why the planet stopped attacking them and allowed them to leave, or so Dr. Chin insists, since clearly there was no such act of love. The End.