The Conscience of the King

Kirk is called to Planet Q by an old friend, Dr Thomas Leighton, who believes the actor Anton Karidian is Kodos, the governor who ordered the execution of colonists during a famine on Tarsus IV years before. Kirk is one of the few surviving witnesses who saw Kodos's face. When Leighton is murdered, Kirk arranges for Karidian's acting company to travel aboard the Enterprise, and grows close to Karidian's daughter, Lenore. Another witness, Lt Kevin Riley, is poisoned, and Kirk himself narrowly escapes a sabotaged phaser. Spock and McCoy grow alarmed as Kirk keeps his suspicions to himself. Riley, recovered, sets out to kill Karidian during a performance of Hamlet, but Kirk stops him. The killer turns out to be Lenore, who has been eliminating the witnesses to protect her father. She tries to shoot Kirk, but Karidian steps into the blast and dies. Lenore loses her grip on reality, believing her father is still performing.