On a mission to establish diplomatic relations at Star Cluster NGC321, Kirk and Spock beam down to planet Eminiar 7 to learn that its inhabitants have been at war with a neighboring planet for over 500 years. They can find no damage nor evidence of destruction but soon learn that their war is essentially a war game, where each planet attacks the other in a computer simulation with the tabulated victims voluntarily surrendering themselves for execution after the fact. When the Enterprise becomes a victim in the computer simulation and ordered destroyed, Kirk decides it's time to show them exactly what war means. Written by
Did You Know?
When Mea 3 escorts the landing part from the beam-down area to the council chamber, the transition of scenes is conveyed not through a cut or a dissolve, but through a wipe-the only time such an effect was used in the original series. See more
Ambassador Fox and his aide beam down to the planet even though the "Enterprise's" deflector screens are up - it was stated that transport could not take place under those conditions. However, Mr Scott had moved the Enterprise further out into space, in a wider orbit, where sonic disruption was impossible. The locals even acknowledged that they could not attack the ship. Therefore, it is reasonable that screens could be opened briefly for transport. See more
The best diplomat I know is a fully activated phaser bank.