Captain Picard and Dr. Crusher prepare to look into a diplomatic request from the Kes, one of the planet Kesprytt's two societies, who want entrance into the Federation. This is unprecedented because the planet's other society, the Prytt, wish no contact with the Federation or anyone else. Worf attempts to transport Crusher and Picard to the Kes, but they end up in a Prytt prison cell, where strange electronic devices are implanted in their necks. Minister Lorin of the Prytt informs Picard and Crusher that they are being held because of suspected conspiracy with the Kes and that the devices in their necks will reveal the truth. Back aboard the Enterprise, Riker sets up a meeting with Kes Ambassador Mauric to address the abduction. Meanwhile, Beverly mysteriously receives her tricorder hidden in a tray of food. She notices that a map has been added to her directory and, sensing it may come from the Kes, she and Picard use it to escape.

Riker, Worf, and Deanna Troi meet with Ambassador Mauric, who tells them that since they have no formal relations with the Prytt, their best option is to insert a rescue team into the Prytt capital city. Meanwhile, Picard and Crusher follow the tricorder map through a maze of caverns where fireballs explode around them.

The Enterprise is contacted by Lorin, who refuses to discuss Picard and Crusher and threatens an attack if Riker does not cease communications with her people. Even though Worf's analysis shows that the Prytt weapons are no danger to the Enterprise, Riker is at a loss until Mauric informs him that Picard and Crusher have been released by a Kes operative and are on their way to the Kes border. Meanwhile, Picard and Crusher realize that the implants in their necks allow them to read each other's thoughts — whether they want to or not. When they separate to regain privacy, both are hit with nausea that renders them incapable of being apart.

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Wikipedia