Plot summary
USS Voyager 's holographic doctor is activated due to a red alert. Despite the computer 's assertion that nobody is aboard, B'Elanna Torres soon arrives in sickbay. She informs the Doctor that the ship was attacked by Kazon and that all except herself and Captain Janeway have abandoned ship. After treating her injuries, Torres transfers the Doctor's program to the bridge, using newly-installed holographic emitters there. The Doctor treats the captain and further assists Neelix to defeat a stray Kazon in the mess, but then notices he is bleeding and feeling pain, neither of which is a function of his programming. In sickbay, making inquiries with the computer, the Doctor is told that there are no holographic programs matching his own and that he is actually Lewis Zimmerman, whom the Doctor recognizes as his programmer.
With the computer insisting that the crew of Voyager is only a collection of holographic programs, a new hologram appears in sickbay and claims to be Reginald Barclay, Doctor Zimmerman's assistant at the Jupiter Station Holoprogramming Center. Barclay explains that the Doctor is really Lewis Zimmerman and that the Voyager is just a simulation in which he has been trapped and which is inflicting radiation poisoning. To end the program and rescue Zimmerman, Barclay suggests destroying the ship before he suffers irreparable brain damage. To convince the Doctor that he is Zimmerman in a simulation, Barclay restarts the Voyager program, and the Doctor finds himself reliving the events of " Caretaker " when he was first brought online.
Convinced of Barclay's claims, the Doctor prepares to destroy the ship, when Chakotay arrives and gives an alternative story: the Doctor is indeed the Voyager EMH, but his program is stuck in the malfunctioning holodeck. The crew is trying to extricate his program and he only needs to wait; if he destroys the ship as Barclay suggests, it will prematurely end the program and the Doctor will be lost. Even though Barclay introduces Kes as Zimmerman's wife, the Doctor finally opts to believe in his holographic existence. The simulation ends and the Doctor finds himself on the holodeck; Chakotay's story was true and the Doctor is safely returned to sickbay.
Credits
Adapted from Wikipedia contributors, Projections (Star Trek: Voyager). Paragraphs and formatting adjusted; illustrations, reference markers, block quotations and non-story material omitted.