Gamma Quadrant humanoid species living near the Idran Terminus of the Bajoran wormhole. The Mohnians were afraid of the Dominion and had been under their thumb for many years. After the war they were tricked into believing the Dominion still controlled them by an unscrupulous Vorta, Vromir, and his small group of Jem'Hadar. They were forced to build an artificial wormhole, which irradiated their planet with Beltane radiation, and also to produce Ketracel-white.

An away team from the Potemkin, the trapped in the Gamma Quadrant, help get rid of Vromir and to spread anti-radiation medicine to the Mohnians.