Federation vessel operating during the time of the Romulan-Cardassian War. It had been serving on the front lines for some time and was on its way back toward the center of the Federation when it received a mysterious communication. The communique turned out to be some virus and it began to systematically brainwashing half of the crew to believe the other half were Romulans.

Someone on board managed to send out a distress call that they were being boarded by Romulans. The Potemkin responded and was damaged heavily by the remaining Dartmouth crew who thought it was a Romulan warbird. An away team was also trapped on board and taken captive by the confused crew.

The Dartmouth fled at warp, but was eventually tracked down and, using the the pre-fix code, disabled. The ship was flooded with anesthezine gas and the crew taken into custody.