To end a centuries-long war, the peoples of the planet Krios and Valt Minor have agreed to participate in a Ceremony of Reconciliation to be hosted aboard the Enterprise. Kriosian ambassador Briam arrives first, and asks that special care be given to his cargo as it is considered irreplaceable. As they travel to meet the Valt delegate, the Enterprise encounters a failing Ferengi ship and brings its two crew aboard, which Captain Picard assigns security to watch closely. Despite this, the Ferengi manage to enter the cargo bay where Briam's cargo has been kept, and inadvertently deactivate a stasis field on one of them, revealing a young Kriosian woman. Commander Riker helps to secure the Ferengi and helps the woman, who reveals her name as Kamala, an empathic metamorph that can sense what males around her desire and react appropriately. Her body is soon to be at the cusp of her ability where she will bond with the Valtian representative, and as such, she is generating pheromones that can affect males around her, which was why she was kept in stasis until the Ceremony.
Briam tells Kamala to stay in her assigned quarters until the ceremony, but Captain Picard takes note of her disappointment, and allows her to venture through the ship, with Commander Data, unaffected by her pheromones, acting as her escort. After avoiding altercations in Ten Forward with the ship's male civilian passengers, Kamala goes to visit Picard. Her empathic nature causes Picard to become closer to her. The Ferengi attempt to get Briam to turn Kamala over to them, since she's an answer to a Ferengi prayer, and Briam appreciates their offer; when he turns to leave to discuss it with Picard, the Ferengi attempt to restrain him, in a last-ditch effort to negotiate, and injure him. The Enterprise turns the Ferengi over to the nearest starbase to stand trial, but Briam is too injured to participate in the ceremony.
Kamala suggests Picard take on Briam's role, and she helps him to prepare, strengthening the relationship between them. Kamala is intrigued by the Captain. She actively pursues him and proves to be a match for him on many levels; most especially intellectually because she has been trained and educated in numerous subjects including archaeology and literature which are two of the Captain's passions. As the two spend more time together, Captain Picard attempts to resist Kamala's charms and tells Kamala to not do "this thing you do with men." Kamala counters that it is in her nature to change her personality to meet the needs of the man in her life. Kamala further says that the Captain knows her better than realizes; for she is adventurous, brilliant, forceful and independent; just as he would have her be. As The Captain prepares for the ceremony, he and Kamala share a few personal details and Picard ventures that her life must have been lonely with other people's expectations being forced upon her. She counters that the opposite is true, she has always servants and tutors with her constantly and finds it ironic that she should meet a man like Picard days before an arranged political marriage.
Soon, they meet with the Valtian ambassador, Chancellor Alrik, who is less worried the marriage formalities and more interested in assuring trade agreements are signed. Picard and Alrik establish the necessary agreements to end the war. With Alrik ready to depart as soon as the negotiations are completed, Picard goes to Kamala to say his goodbyes. He is surprised when she reveals that she has permanently bonded with Picard. She assures Picard that she will be able to please Alrik with her empathic abilities and will never tell him of their bond, but some of the aspects she gained from her bond with Picard will carry over such as his love of William Shakespeare and his commitment to honor and duty. Following their departure, the Enterprise returns Briam to his home planet. Befrore being transported home, Briam confides in Picard that he was impressed that he did not fall for Kamala's charms, but Picard remains quiet on the matter.
Ironically, the alien makeup Janssen wears in this episode (the spots on her face) were actually used for Jadzia Dax when that character was introduced, as Terry Farrell was allergic to the original Trill makeup from "The Host".