Public Relations Nightmare
    This idea could be fitted in anywhere into the proper campaign, but it best used for one that is set around Yavin (when the Rebels were enjoying success, but had little kit). It is delivered like a "breaking news flash," with reporters on the scene of a major explosion, on a planet that has had some open support for the Rebellion, but not a lot. It should be set around a planetary holiday (such as the Landing Day of the first colonists). For the holiday's parades and celebrations, the Empire has sent several units of troops and one of the Empire's highest leaders/heroes. I'd almost say Vader and/or Tremayne for the leaders (they could have even put on a demonstration of lightsaber sparring), and the demonstration troops should include some thing like the Imperial Guard Drill Team (like the Marine Corp Drill Team, but in pretty red armor).

    The Imps respond to the explosion with a massive show of support, like sending the troops and the celebrities to help with the rescue operation, with space troopers doing heavy lifting and debris clearing, opening the medical bays on the garrisons and orbiting ships to the victims, our Dark Sider trying to revive people and moving speeder-sized pieces of permacrete, etc. One shot that you MUST have is one of the Guardsmen (or whatever), with his robes tattered at the hem, his armor heavily scuffed and scratched, his helmet cracked open by falling debris (witch happens to expose his face), carrying the body of a young child, with tears streaming down his face. Maybe even add a minor head wound (like a gashed forehead) and making him fairly attractive looking.

    Your PCs are on planet to coordinate with sympathizers (organizing cells, getting supplies, whatever fits). How do they deal with this major PC crisis? Was it an extreme branch of the Rebellion, the Imps, criminals or just a gas leak? Will it jeopardize the negotiations? Will one of the sympathizers turn away from "a mob or baby killers," and try to lead the Imps to the characters? Alternatively, will he try to give classified data to the Imps (a cargo route, personnel files, etc.)?

    This should give you plenty of area to play with, but it should need a minimum level of shooting and looting. 1