Jon Stephens

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Lieutenant Jon Stephens was an alias taken by Lady Q when she visited the USS Enterprise-E in 2380 in order to be a direct participant in the battle against the super-sized Borg Cube. "Stephens" claimed to have been born on Mars and served as Conn officer on the Enterprise. Part of the fabricated history for Stephens included the "fact" that he transfered off the USS Excalibur-A for being too "strange" for Mackenzie Calhoun's crew. (TNG novel: Before Dishonor)

The deception (but not Stephen's true identity) was revealed during a meeting between Captains Calhoun and Picard on Earth following the destruction of the Borg Cube, when Calhoun informed Picard that he had no idea who Stephens was and that he did not transfer him to the Enterprise. Stephens true identity was revealed only to Kathryn Janeway during a conversation after Admiral Janeway's "death". (TNG novel: Before Dishonor)