The Enterprise visits Caldos IV to enable Dr. Beverly Crusher to attend the funeral of her grandmother, Felisa Howard. During the burial, Crusher sees a man she does not know who is obviously very interested in the events. Later, Crusher enters her grandmother's house and collects several mementos, which she takes onto the Enterprise. Reading some diaries, she discovers that despite being 100 years old, her grandmother was involved with a 34-year-old man named Ronin.

Back on the planet, a groundskeeper of her grandmother's tells her that there is a ghost in her grandmother's house and that she should leave immediately. He also tells her that she never should light the candle her grandmother always carried, since this candle will wake up the ghost. Beverly hears a voice that tells her he is a ghost and loved her grandmother and now also loves Beverly. Finally he becomes visible, and Beverly sees a man of about 30 years.

Meanwhile, the colony is suffering from a major storm system, which the weather modification satellite is unable to correct. Data and Geordi attempt to fix the problem but are shocked to find Ned, the Howard groundskeeper, trying to stop them, before he is killed in an explosion.

The ghost called Ronin manipulates Beverly's mind so that she falls in love with him. Ronin tells her to light the candle, which is on the Enterprise. Beverly beams up and lights the candle, and Ronin appears. Beverly tells Captain Picard that she wants to leave the Enterprise and live on the planet. Reluctantly, Picard agrees. Picard goes to Counselor Deanna Troi, with whom Crusher spoke about Ronin before she left.

Troi tells Picard that Ronin is a very strange man, but they have to accept Beverly's decision. Then Picard beams down onto the planet and visits Beverly in her house. He wants to get to know Ronin, and finally Ronin appears. Picard asks questions which Ronin does not want to answer, and Ronin attacks Picard. Despite Ronin's objections, Beverly helps Picard.

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