The Resistance Hidden Agenda
The Resistance Hidden Agenda is an expansion for your games of The Resistance which is needed in order to play. This expansion adds three modules which you can use in any combination to your games. Get both The Resistance and the expansions at a discount by purchasing the Resistance Bundle.
Similar to Merlin in the King Arthur themed standalone version The Resistance Avalon, this introduces a Commander who knows who all the Spies are. However his has to remain undiscovered as if the Spies and Assassin can identify and kill him then they will win.
Add two Defectors to your game who have the ability to switch their allegiance between factions which makes it even harder to know who to trust. There is also a second variant where there two Defectors are aware of each other and both can use this knowledge to throw around even more accusations and confusion.
When using the Trapper Module an extra player is sent on every mission and the Leader has to pick one to isolate them from the result. Players will have to trust the judgement of each mission leader to isolate the spy after approving a mission knowing that at least one is part of the party.