Interrogation
This is an action accessible as an Interact option, only currently available for NPCs who have the Secretive trait.
Interrogation attempts can be either Persuade or Threaten.
Each attempt takes 18 minutes, and there is no limit to the number of attempts per day, except as constrained by Stamina.
Persuade attempts use the MC's Manipulate skill versus the NPC's Willpower, modified by the NPC's Kindness and by the number of Followers the MC has assisting him. Attempts cost the MC 2 Stamina points, and if successful will reduce the NPC's Secretive trait value by 12 points. Successes also have a good chance of increasing Affection by +2 points, and will reduce Anger by 2 points if it is above 4.
Threaten attempts use the MC's Manipulate skill versus the NPC's Willpower, modified by the MC's Power Value, the number of Followers the MC has assisting him, and whether the NPC is naked (only available if the NPC is female). Attempts cost the MC 4 Stamina points, and if successful will reduce the NPC's Secretive trait value by 20 points. Successes will also reduce the NPC's Willpower by 1 point (down to 20), reduce their Affection by 5 points, and affect their Fear.
Once an interrogation is complete (having reduced and NPC's Secretive trait value to zero), a secret will be revealed, which will be added to the MC's Character Sheet quests Journal.
Each "Secretive" person will have a different secret. You can interrogate multiple people at a time, and make progress on uncovering their secrets, but only one secret can be revealed at a time. So you won't be able to discover the secret of a person being interrogated if there is still an unresolved secret from the last interrogation in your Quests journal.