Background
They were two Corellian street rats, Jugo and Jamba. They liked to call themselves the Booster Brothers, thinking it gave them a sort of roguish charm, but they were just two more petty crook street kids, and everyone knew that. Everything changed when they saved the life of a hot shot Bothan slicer by the name of Mirin.
Mirin ran afoul of a group of neo-anarchist troublemakers called the Warriors, who were spread in dribs and drabs across the face of Corellia. It was stupid really. Both were in line at a kebab shop, the best in Corellia. The Warriors were taking an agonizingly long time to order and pay. Mirin made a comment. They made comments back. Parentage and sexual prowess and proclivities were disparaged. Things degenerated. Mirin was expecting his rep to protect him. The neo-anarchists didn't care. His rep did still save him, because it made Jamba and Jugo jump in.
With Mirin in their debt Jugo and Jamba planned a heist. They had an idea, one that would both put them on the map, and get them off Corellia. The Admiral in control of the Corellian sector was a man much unloved by the people under his “protection.” He was however something of a connoisseur of ships, perhaps the only thing he had in common with Corellians. His personal “captian's launch” was a HWK-290 lovingly restored, and with a well appointed saloon taking up the former cargo bay. As both a shuttle and a personal pleasure craft, he was quite fond of the ship.
Juggo and Jamba, with the help of Mirin, stole the ship.
Mirin altered the ship's registry and engines, cloning it to another of the ships still out there, and the two were out of Corellian space almost before Admiral Poniff knew what happened. They were free to explore and make a name for themselves as skilled and savvy smugglers, or so they thought. The Booster brothers horribly underestimated both how much Poniff wanted the ship and those that took it, and how thoroughly the Empire could search for something.
They were free and clear for a while, a year or two if memory serves, before their names and faces wound up on Imperial wanted lists. The brothers made for the rim, as one often does in these situations, and for a time managed to evade the imperials and bounty hunters.
Only for a time though.
Eventually the Imperials caught them in a trap. Jugo managed to escape, but Jamba did not. Jamba was taken to Crematoria, a prison planet that is perhaps second only to the Kessel mines for “places you don't want to wind up.”
Never much of a fan of the Empire even before they imprisoned his brother in some hell hole (almost literally), Jugo has taken up working for the Rebel Alliance. The deal is that he'll smuggle for them, and they'll figure out a way to get his brother out of Crematoria. It's been a while, with no sign that the Alliance is actually doing much of anything to fulfill their part of the deal, and Jugo is starting to loose patience.
Motivation
Get brother out of jail.
Earn Cred.
Have fun.