In the midst of a ceremony celebrating Tuvok's promotion to Lieutenant Commander, Voyager receives an automated distress call sent by Dejaren, an alien hologram, who says that his crew is dead and he needs help. The Doctor, anxious to meet a fellow hologram, tracks the source of the transmission and is assigned to the rescue mission along with Torres. Upon their arrival on the disabled Serosian ship, they meet Dejaren, who is pleased to see another "lifeform" like himself.
The hologram says that his crew became infected with a deadly virus, which killed them all. Dejaren is awed by the Doctor's freedom and abilities; his crew never let him out of his chamber or treated him as anything other than machinery. Later, as Torres works to repair Dejaren's systems, Dejaren lashes out at her verbally, castigating her organic body and way of life. Torres shares her concerns about the hologram with the Doctor and informs him that Dejaren lied about the lower deck being filled with harmful radiation. Perhaps there's something down there that he doesn't want them to see. Although the Doctor empathizes with his fellow hologram, he agrees to keep Dejaren occupied while she investigates.
As he talks to Dejaren, the Doctor begins to realize that Torres was right. The hologram is pathologically bitter toward "organics." On the lower deck, Torres finds the bloody bodies of the crew and it's clear they didn't die from a virus. As she hurriedly tries to deactivate Dejaren's program, the homicidal hologram appears and nearly kills her before she manages to shut him off.
Meanwhile, aboard Voyager, Harry Kim is assigned to work with Seven of Nine on the new Astrometrics lab. Kim is uneasy working with the Borg, but their detail provides them with the basis of a friendship. However, Kim is rattled when Seven of Nine interprets his pleasantries as romantic seduction and she decides to further explore her resurgent humanity.
On the Serosian ship, the Doctor and Torres find that the hologram has disabled their communication link to the shuttle. As they work to restore it, Dejaren reactivates himself and knocks out Torres. He disconnects the Doctor's mobile emitter, causing the Emergency Medical Hologram to disappear. Torres awakens and flees, but a murderous Dejaren pursues her. Finally, she manages to destabilize his matrix with an isomagnetic conduit, deactivating him for good, and brings the Doctor back on-line. Both return to Voyager with a new appreciation for the Doctor's unique — and stable — personality.