Your contact has a simple job for you, travel to Bespin, pick up a crate the Ugnaught Surface, bring it to Corellia, and don't ask any questions. Shouldn't be a problem, except the planet has recently fallen under Imperial subjugation.
A LongCon is a multi-session RPG adventure that spans the course of the convention. Play in all of the sessions to follow the whole story or drop in and out of sessions to get a taste of the adventure!