Cover story
A cover story was a made-up explanation for one's presence in a location where one was otherwise not supposed to be, or for an operation whose true purposes were to remain a secret.

In 2063, Deanna Troi told Zefram Cochrane her cover story, which he didn't believe. ()

In 2377, Chell speculated that the comas which several ex-Maquis  crewmembers had lapsed into were in reality a front for orders from Starfleet Command to neutralize the Maquis threat on Voyager. B'Elanna Torres found the theory to be ludicrous. ()

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Maneuvers