"Aquiel" is the 139th episode of the American science fiction television series Star Trek: The Next Generation, the 13th episode of the sixth season.

Overview: The crew of the Enterprise investigates a mysterious death on a remote station, and Commander La Forge falls for the main suspect.

The Federation starship Enterprise arrives at a subspace communications relay station near the Klingon border on a resupply mission. However when an away team boards the relay there is no sign of the two officers assigned there. Lieutenant Aquiel Uhnari, Lieutenant Rocha and the station's shuttlecraft are missing. While searching, the station the away team finds the dog that belongs to Lieutenant Uhnari. The away team also finds a substance on the floor, which Enterprse Chief Medical Officer Dr. Crusher determines is a type of cellular residue.

The crew uncover evidence that a Klingon had been on the station leading Crusher and First Officer Riker to suspect that Uhnari and Rocha may have been the victims of a Klingon attack. Commander La Forge backs up this theory when he examines Uhnari's personal logs. He finds an entry in which Aquiel relays her fears to her sister Shianna about a Klingon named Morag. Captain Picard contacts the local Klingon governor, Torak, and learns that Morag is commander of one of the Klingon ships that patrols that section of the Klingon Empire's border. At this point, Torak refuses to cooperate further. Picard threatens to take his case to Chancellor Gowron, a threat scoffed at by Torak until Picard casually mentions that he served as Gowron's Arbiter of Succession. Knowing Gowron would be in Picard's debt and how the former might frown upon the disrespect shown to the latter, a nervous Torak agrees to cooperate fully.

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