Han Solo: We’re caught in a tractor beam. It’s pulling us in.
Luke: There’s gotta be something you can do.
Han Solo: There’s nothing I can do about it, kid. I’m full power. I’m gonna have to shut down. But they’re not going to get me without a fight.
Obi-Wan: You can’t win. But there are alternatives to fighting.
The group decides to make a Stealth check to hide from the Imperials. Han Solo makes a check for the group, with a bonus from the smuggling compartments on the Falcon. Stormtroopers search the ship, but their Perception check fails compared to the Stealth check. An Imperial lieutenant checks the ships logs, but the Stealth check rolls forward and his Computer Use check fails compared to it (so the logs show that the ship was abandoned shortly after takeoff).
Darth Vader issues an order for a scanning crew. Before they arrive, the PCs emerge from the smuggling compartments. They lose that bonus from their Stealth result, but the result itself continues to roll forward and allows them to ambush the scanning crew when it comes onboard. The PCs decide to take their uniforms (giving them a disguise bonus to their Stealth result).
At this point, however, there’s a point of uncertainty: The operators in the control booth try to contact TK-421 over the radio. The PCs decide to make a Bluff check to convince him that their radio is malfunctioning. The check is a success and it even convinces the operator to open the control booth.
Now there’s a brief interruption while Chewie and Han take out the control booth operators and then R2-D2 hacks the Imperial network to learn the location of the tractor beam.
Obi-Wan splits off from the rest of the party to deactivate the tractor beam. Han’s Stealth check continues to ride forward, but Obi-Wan is off by himself so the GM asks him to make a separate Stealth check (which will also ride forward).
Continuing his hack, R2-D2 discovers that Princess Leia is held in the detention block and is scheduled for execution. Luke convinces Han to help him rescue Leia, but they decide to increase their chance of reaching the detention block undetected by continuing their pretense of being stormtroopers with Chewbacca as a prisoner. Since this is the same disguise that they used earlier, the result of their Disguise check also rides forward and continues granting them a bonus to their Stealth result.
The result easily lets them move through the halls of the Death Star. The GM tries to add a complication by having someone board an elevator with them, but Han waves him off by suggesting that their prisoner is too dangerous.
The PCs arrive in the prison block. The GM makes a Perception check (or possibly two) for the guard on duty: Their Stealth check holds up, but their Disguise check isn’t good enough. He’s suspicious. This is another point of uncertainty, but this time they blow their Bluff check (“Prisoner transfer from cell block 1138.”) and he’s going to check their story.
Combat! Laser fire everywhere!
But that triggers a new point of uncertainty: They’ve set off alarms and someone is calling to see what the problem is. Han tries another Bluff check… and blows it again. The Stealth check stops rolling: “We’re going to have company!”
Luke opens the cell door. Princess Leia wakes up, makes a Perception check against the riding Disguise check, and succeeds. “Aren’t you a little short for a stormtrooper?”
Luke rips off his helmet. And, at that point, the Disguise check also stops rolling forward. (The PCs are changing their approach.)
R2-D2’s Hack check and Obi-Wan’s Stealth check, on the other hand, are still rolling along merrily.