The plan is:
1. The party emerges, and sees Karcero fighters circling. They also get signals from the local rebels trying to contact them (because the party was out of communication while in the facility). The rebels have ships inbound to help, but they're a few minutes out. The PCs basically have two shuttles versus a lot of fighters. I need to figure out the balance and difficulty.
2. The enemy ships are one round out, so the party has a short period of time to make plans. They're in the mountains, right at the snow line, and the cloud cover is fairly low, so perhaps they could lose their enemies in the clouds around the mountain peaks. Or they can head south, past the Jedi temple ruins, for flatlands where their enemies can shoot them better, but their allies will arrive more quickly.
3. Suddenly strange gravity fluctuations start ripping rocks out of the ground, and if they're above the cloudcover (or bother to scan upward) they see that the Star Destroyer with its gravity interdiction field is descending into the atmosphere. There's too much interference (due to atmospheric friction) to hack into the ship, but basically when the droid was shut down, it triggered a failsafe, ordering the vessel to descend near Sareve's ship, so that she can get aboard. The Star Destroyer will below the cloud cover in three minutes (three rounds). And its descent will take it directly into the path of the party's rebel allies.
4. Let the dogfight begin, with Dune's fighters trying to take out the PCs. Or possibly a chase.
5. After a round or two of dogfighting, Dune himself arrives - traveling on his own personal shuttle with fighter escort. At this point his goal is simply to kill the PCs, then escape. Because the cargo bay door of Sareve's shuttle is jammed open, I kinda want him to jump on board with some bodyguards and have a melee battle in the midst of the dogfight.
6. When the Star Destroyer clears the atmospheric interference, the tech PC will be able to reestablish his link, wherein he discovers that the crew is not responding, like they're all dead. Sensors detect some weird readings emanating from the gravity field generator, nothing he's ever seen before.
7. More fighting. Reinforcements are almost here, but then their comms go silent, and the rebel fighters just glide onward, like on autopilot. The party might realize that whatever weird energy the Star Destroyer is putting out, the rebels just flew into its radius, and now they're non-responsive, just like the imperials.
8. One more round of fighting, or talking, or planning. But then the Star Destroyer, which is far faster than the PCs' vessels, comes within range of Sareve's shuttle, and everyone on board (and anyone else nearby) finds themselves in a dream.
The Imperial research facility's most critical project was 'The Phantom Drive,' intended to subtly warp the fabric of reality in order to make a ship invisible. Instead, it creates a pocket in the fabric of the Force, causing any living creature to fall unconscious and have its soul float through a psychic landscape -- in this case, a seemingly empty Star Destroyer. Everyone who was aboard is now roaming their own labyrinthine mindscape that resembles the Star Destroyer, believing themselves alone except for occasional shouts of others who are trapped there, which seem to come through the walls. However, creatures that are Force sensitive have some control over this place, and so Hank, the Force-sensitive PC, will see a vision of a glowing floating baby, who guides him to locate the rest of the party. He'll be pursued by Dune Gomero, who instead of fighting will offer to train Hank, to guide him so the Force can set them both free. Occasionally they'll come across Imperials who believe they've been here for years. When they find the Senator, the force baby glides into her belly, and she's suddenly granted understanding to explain what's going on.
They'll need to find the physical 'Phantom Drive' in the engine room and deactivate it, and at the side of the device they find a specter of sorts - Sareve, whose spirit persists enough for her to snarl at the pregnant Senator and try to kill her. If Hank has refused Dune's offer, he fights too, trying to slay the Senator while doing the villainous 'taunt+exposition' thing to explain that her child is strong in the Light side, and if it dies here, it will permanently strengthen the Dark side.
If they turn off the machine, they snap awake back in their bodies, with only moments having passed. Saving the child will heal them all and blind Dune. Killing the child will kill the entire crew of the Star Destroyer and cause the surviving PCs to be haunted.
Yes, it's surreal. I need to work on it so I can pull it off properly.