The crew of Serenity take on a train heist commissioned by a crime lord. They steal the goods, only to find it is medicine that's desperately needed by the town.
In the year 2517, after the arrival of humans in a new star system, follow the adventures of the renegade crew of Serenity, a "Firefly-class" spaceship. The ensemble cast portrays the nine characters who live on Serenity.