Lwaxana Troi returns to the Enterprise, this time as the teacher of an alien race learning to speak. Their native form of communication is telepathy, but they want to learn spoken language in order to interact with other races. Lwaxana comes aboard with Maques and his young daughter, Hedril, who is Lwaxana's star pupil.
Suspecting that Lwaxana is not her usual, flamboyant self, Deanna tries to investigate. When Lwaxana starts showing signs of fatigue, she is taken to Sick Bay to be examined. Beverly tells Lwaxana that her interaction with the aliens is more taxing on her telepathic glands than she is used to and is asked to refrain from telepathic contact with them until she can recover. Deanna helps her mother by verbally communicating with Maques and Hedril, but Lwaxana still uses her telepathy when they don't grasp the verbal concepts. After an incident where Hedril falls into a pool of water in the arboretum, Lwaxana falls into a coma. With no signs of physical trauma, Crusher deduces that her telepathic abilities have caused her mind to collapse in on itself from the over use. Maques uses his ability to form a bridge between Deanna and Lwaxana, and the former finds herself walking through corridors like on the Enterprise. Lwaxana's mental defenses pick up, first conjuring Deanna's father to distract her, then an image of Picard himself ordering her to sever her connection. She sees past these ruses and encounters Hedril petting a wolf, but the girl does not seem to know who "Hedril" is. Lwaxana then charges in screaming for Deanna to get away from her, causing Deanna to break her connection.
Deanna and Riker search through Lwaxana's things and find several pieces of the puzzle missing; journal entries for a journal Lwaxana kept since being married had blank pages from shortly after Deanna's birth going on several years. The image of Hedril in her mother's mind does not add up. She tries again to reach her mother, this time, Deanna encounters the wolf by himself who chases after Deanna through the deck until she encounters a Turbo Lift that opens into space. Hearing her mother call for help, Deanna jumps in and lands in the arboretum where Lwaxana had collapsed. Lwaxana is there, still begging Deanna to leave, but Deanna refuses, stating that a repressed memory is killing her and she must relive the memory in order to survive. Suddenly, an image of a human girl who looks like Hedril is playing by the water with a puppy, and Lwaxana calls her Kestra. Deanna urges Lwaxana to relive what happened, and she tearfully remembers a tragedy when Kestra ran after the puppy when it got away, though it was unclear what had caused her death. Lwaxana's repressed memory of Kestra and her resemblance to Hedril led to her coma. As Lwaxana recalls happier memories of Kestra, Deanna tells her to share them so she can learn about the sister she never knew. The women awaken in Sick Bay holding hands.