Secret Kept for Someone Else

Your players need someone interesting, not another quest-giver. This builds an NPC who's keeping someone else's secret, with a clear reason they chose loyalty over honesty, a visible cost the secret is exacting, and the exact moment they'd crack and tell the truth. Drop them into a campaign and watch the players circle.

Create an NPC who is keeping a secret that belongs to someone else. They are not the one with something to hide, they are the one doing the hiding. Give them a clear reason why they chose loyalty over honesty, a visible cost the secret is taking on them, and the exact moment they would break and tell the truth.