Anton Karidian was the alias assumed by Kodos, known as "Kodos the Executioner" after the massacre at Tarsus IV. His daughter Lenore Karidian was born one year after the massacre, and always bore the surname Karidian. At some point after assuming this identity, Karidian formed the Karidian Company, a troupe of itinerant actors.
In 2266, the Karidian Company visited Planet Q. One of the residents of that world was Thomas Leighton, who recognized Karidian as Kodos. He asked James T. Kirk to investigate, as Kirk was one of the nine people who actually saw Kodos. After a series of murders and attempted murders, Kirk was convinced that Karidian was Kodos and was killing witnesses to cover his identity. In actuality, it was Lenore who was committing the crimes, and when she tried to kill Kirk, Karidian jumped in the line of fire as she fired a phaser, killing him. (TOS: "The Conscience of the King")