The wife of the research scientist Thomas Leighton on Planet Q, who hosted the reception for the Karidian Players in 2266 and was widowed that night when her husband was murdered.
Martha Leighton appears in The Conscience of the King. She lives on Planet Q with her husband Thomas, one of the few survivors able to identify Kodos, the former governor of Tarsus IV.
She is hostess at the cocktail party the Leightons give for Anton Karidian's acting company, an evening her husband has arranged so that he and Kirk can study the actor at close quarters. Karidian does not attend, and Kirk meets his daughter Lenore instead. Later that night Kirk finds Thomas Leighton stabbed to death outside.
In a brief scene afterwards Martha tells Kirk that her husband had lived for years with the memory of the massacre and that it finally consumed him. She was played by Natalie Norwick.