SG-1 helps transfer the residents of a Goa'uld slave planet to a new world, but soon find the planet is the target of a terraforming effort that will wipe out its new inhabitants.

Martin Lloyd, a conspiracy nutjob, calls up the SGC but has accurate knowledge of the Stargate. Martin claims to own a spaceship and is dismissed as a crackpot, but a series of incidents suggests that there may be more to his claims.