- Escape temporarily with a group
- Find scrolls of modify memory
- Remove memories from all but one escapee
- Rest of the group returns home with no memory of escape or the person left behind
- Escapee on the outside learns the spell modify memory and/or finds more scrolls
- Returns to orchestrate resistance
- The resistance operates in cells which have no memory of being part of the resistance
- "Handlers" are rotated frequently and are responsible for providing memories and stockpiled weapons
- Cell members are given memories, perform missions, and then return home with no memory
- Cells that are compromised are abandoned immediately and their members are never activated again.
- Handlers are personally recruited and serve for short periods of time before being wiped by the next handler.
Seems like a pain, but possible. It would make a good story.