"Pathfinder" is the tenth episode of the sixth season of the science fiction television series Star Trek: Voyager, 130th episode overall. It features the characters Reginald Barclay and Deanna Troi from Star Trek: The Next Generation. Paris's dad Admiral Paris played by Richard Herd, makes contact with his son. This also marks a continuation of the story arc of Picard's Enterprise with contact between Voyager crew and Barclay who had served aboard the Enterprise D, and first contact with Earth by Voyager since Message in a Bottle (S4E14).

Previously, the Star Trek character Reginald Barclay had appeared in the Voyager show in Projections (S2E3), however, although played by the same actor in that episode it was a holographic simulation of Barclay. The same actor playing as Barclay had appeared in cinema in the feature film Star Trek: First Contact (1996).

On Earth, Reginald Barclay is involved in the Pathfinder project, an effort to communicate with the USS Voyager stranded in the Delta Quadrant. Barclay soon becomes obsessed. He loses himself in the reality of the holographic Voyager created for the project, enjoying the false friendships within.

He seeks help from old friend and shipmate Counselor Deanna Troi who advises him to forge real relationships and stop straying into the holo-program he has created of the Voyager ship and crew. When Admiral Paris visits the project to inspect progress, Barclay ignores orders from Commander Harkins, the project leader, not to bother the Admiral with his unfeasible suggestions. Barclay puts forward his theory that using the MIDAS Array (an advanced sensor array), and computing Voyager's progress from their last contact, they would be able to create a micro wormhole in the Delta Quadrant near Voyager and use it to create a two way communication link. Admiral Paris is intrigued by this and promises to give it further study which Barclay is highly excited by, but at a later meeting with Admiral Paris, Barclay oversteps the line and is removed from the project for insubordination.

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