Upon receiving a distress signal from a Romulan science ship, Picard surprises some crew members by sending an Away Team to help. The Romulan officers are also surprised, but are also relieved to be rescued. During the mission, Geordi discovers that one of the ship's generators needs replacement, so he and Ro prepare to beam back to the U.S.S. Enterprise to replicate the part. However, something goes wrong during the transport. After dematerializing from the Romulan ship, the pair fail to reappear on the Enterprise. After several failed attempts to bring them back, Picard and the crew are forced to accept the fact that their comrades are dead. Later, Ro mysteriously appears in Sickbay, where Picard and Dr. Crusher are signing her death certificate. She tries to talk to them to tell them she is alive, but they don't hear her. She stands in front of them, but they don't see her. In fact, Picard actually walks right through her. Because of this, Ro concludes she must be dead.
Ro eventually runs into Geordi, who has been having the same strange experiences. Although the pair can hear, see and touch each other, they seem to be removed from the rest of the ship. Ro tells Geordi she believes this means that they are dead, and have returned to the ship as spirits. Geordi, however, refuses to accept her explanation and sets about trying to find a solution.
Data takes on the dual task of planning a memorial service for his fallen crewmates and investigating the mishap that caused their deaths. Geordi is present when Data surmises that the accident had something to do with the accident that occurred aboard the Romulan ship. He and Worf return to the ship to investigate, with the invisible Geordi and Ro secretly tagging along. Once on the ship, the Romulans act very secretive when Data asks to scan their engine room. However, they talk freely once Data leaves the room, unaware that Geordi and Ro can hear everything they say. The invisible pair soon learn that the Romulans are testing a new cloaking device that hides things by dematerializing them. They realize that they are not dead — just accidentally cloaked.
Unfortunately, the pair must find a way to get uncloaked before the Enterprise leaves the Romulan ship's area or they really will be dead. Geordi finds a way back on the Enterprise, when Data notices a high level of chroniton fields on the ship. Geordi realizes that he and Ro create these fields by making contact with objects aboard the ship. He is further encouraged when Data sprays the contaminated areas with a substance that gives Ro and Geordi back some of their substance. They realize they must work to create as many chroniton fields as possible so that Data will spray enough of the chemical to force them to rematerialize. The pair implement their plan at their memorial service, which is more like a huge party. They create a large number of chroniton fields, forcing Data to use an large amount of spray to eliminate them. When he does, their images reappear — but only for a brief moment. Luckily, both Data and Picard see the pair and realize what has happened. They flood the room with the anti-chroniton chemical and Geordi and Ro rematerialize, turning the memorial observance into a celebration of life.