Kirk discovered that actor Anton Karidian was Kodos, the governor who had massacred thousands on Tarsus IV, while Karidian's daughter was secretly killing the remaining witnesses.
Kodos, the former governor of Tarsus IV, had ordered the execution of about four thousand colonists during a famine and was believed dead. In 2266 Kirk, one of the few people who had seen Kodos in person, came to suspect that Anton Karidian, the leader of a traveling Shakespeare company, was the same man.
The company traveled aboard the Enterprise, and an attempt was made on the life of Lieutenant Kevin Riley, another survivor. The killer was Lenore, Karidian's daughter, who was murdering witnesses to protect her father. During a performance of Hamlet she tried to shoot Kirk, but Kodos stepped into the blast and died, and Lenore lost her sanity.