- "The revolution is successful. But survival depends on drastic measures. Your continued existence represents a threat to the well-being of society. Your lives mean slow death to the more valued members of the colony. Therefore, I have no alternative but to sentence you to death. Your execution is so ordered, signed Kodos, Governor of Tarsus IV."
- —Kodos, 2246[src]
Governor Adrian Kodos (also known as Arnold Kodos or Kodos the Executioner) was a 23rd century human man who was the leader of the Federation colony on the planet Tarsus IV in the 2240s decade, and is generally held responsible for the Tarsus IV Massacre.
In the year 2246, Tarsus IV was used as a test-site by the Symmetrists for the Virogen plague. As a result, a deadly famine struck the colony, and there was not enough food for the 8,000 colonists. Kodos staged a Vote of no confidence against both the lawful governor Gisela Ribeiro and her council, then declared martial law, in which he ordered that 4,000 colonists be killed, so that there would be enough food for the rest of the colony to last until Starfleet aid arrived. The order was carried out, just prior to a relief task-force led by the USS Narbonne and USS Enterprise reached the colony. (TOS episode & Star Trek 1 novelization: The Conscience of the King, DSC novel: Drastic Measures, TOS - Enterprise Logs short story: "Though Hell Should Bar the Way", and TOS novels: Avenger, Academy: Collision Course; ENT episode: "In a Mirror, Darkly"; Last Unicorn RPG module: All Our Yesterdays: The Time Travel Sourcebook; TOS reference: The Autobiography of James T. Kirk)
Following the massacre Kodos and his followers fled New Anchorage. During a firefight between his followers and a Starfleet team led by Lieutenant Commander Gabriel Lorca at Kodos's camp a stray phaser shot hit a crate of banned thermite grenades. Kodo's followers Ian Galloway and Fiona Okafor died in the resulting explosion. Their bodies were recovered a short time later, burned beyond recognition. As Kodos had earlier switched his DNA records with those of Galloway's, DNA testing showed the male body as having belonged to Kodos. Kodos assumed Galloway's identity, and was able to slip off the planet the following year. (DSC novel: Drastic Measures)
Kodos turned to the Symmetrists, who provided him with the identity of Anton Karidian. Kodos lived as Anton Karidian until 2266, when he was exposed by Captain James T. Kirk, one of the few remaining survivors who could still identify him. (TOS episode: "The Conscience of the King", TOS novel: A Flag Full of Stars)
- TOS episode & Star Trek 1 novelization: The Conscience of the King
- DSC novel: Drastic Measures
- TOS - Odyssey novel: Avenger
- TOS novel: Academy: Collision Course
- ENT episode: "In a Mirror, Darkly"
- TOS - Year Five comic: "Issue 2"
- DSC novel: Drastic Measures
- TOS - Enterprise Logs short story: "Though Hell Should Bar the Way"
- TOS - My Brother's Keeper novel: Republic
- TOS novel: A Flag Full of Stars
- TOS novel: Foul Deeds Will Rise