In the Gamma Quadrant, Dax and Odo detect an unusual particle field on the surface of an unexplored planet. Transporting to the source, they find an alien village and some kind of reactor emitting the particle field. Colyus, Protector of the colony, explains that Dax and Odo's arrival coincides with the mysterious disappearances of twenty-two people. Odo and Dax are sympathetic to Colyus's plight and offer their help in solving the mystery.