Apparently, an Independent fleet was crippled by the Alliance near the end of the war. The Alliance took the crews off the ships, and put a minefield around the battlefield, but haven't been back yet to scrap or capture the Browncoat ships. (The campaign's taking place mere months after Serenity Valley and the end of the war.) According to the distress call, a few Browncoats managed to stow away on their own ships, in the hope of repairing the crippled warships and continuing the fight. When the PCs eventually decode the distress call, it reads "send food, water and the following spare parts so we can keep fighting."
Cue lots of running around bars, scrapyards and criminal dens as they initially try to prove that they didn't illegally salvage the escape pod from the crippled battleships, then lots of planning as to how they're going to illegally salvage better stuff from the crippled battleships.
Currently, they're on the run from the Alliance (again) after an informant identified Annata Seiryu as the 'butcher of Ezra'. They've got a semi-unwilling passenger, the daughter of one of the possible Browncoat survivors, and are debating whether to just rescue the survivors and give up on the Independent cause, bring the space parts and get those warships going again, or just repair one of the damaged Browncoat ships and flee into the great beyond.
Rules-wise: A few classic problems, like modeling a knockout punch and so on. Need to get working on the combat rules...