The Defiant crashes on a planet while investigation its odd atmosphere, and finds a thriving community of several thousand people. They claim to be the descendants of the Defiant crew. Their history records that the Defiant was thrown back in time when it tried to pass through the atmosphere again, and the crew, with no way home, eventually built new lives here. Now, the Defiant crew faces a decision. Do they choose to repeat the accident and maroon themselves, or erase these people from time?