Episode Title: "DAY OF THE DOVE"
Production Number: 66
Original Air Date: 11-01-68
Captain Kirk leads a landing party to planet Beta Twelve-A, where a Federation colony has disappeared after signalling that it was under attack. A Klingon ship arrives, also responding to a distress signal, and is disabled by internal explosions. Kirk beams the surviving Klingon crew over to the U.S.S. Enterprise, but the Klingon commander, Kang, blames Kirk for attacking his ship.
An alien life force takes control of the Enterprise, locking it on a course out of the Galaxy, and bladed weapons appear throughout the ship, allowing the Klingon passengers to fight the Enterprise crew to a stalemate. Hostile feelings are enhanced, and injuries are healed by the alien life force, so that fighting can continue. Kirk and Spock realize that the alien life force feeds on violence, so Kirk convinces Kang and the other Klingons to stop fighting in order to weaken the alien. With no more hostilities to feed on, the alien life force flees the Enterprise.
Factoid: The Klingon Empire and the Federation have been at peace for three years.
Factoid: Klingons have no devil.
Factoid: According to Klingon saying, "Four thousand throats may be cut in one night by a running man."
Factoid: The Klingon Empire has maintained a dueling tradition, and its warriors are formidable with swords.
Guest Characters: *Kang
Alien Races: Klingons
KEY: [brackets]=illusions *star=first appearance