I have had the handcuffs common item card for ages now, I forget which expansion they came with. I’ve played all the scenarios a few times each now but still haven’t had this item come into play. Which scenario uses them ?

I recently played the Twilight Diadem scenario and they came into play.

I won't spoil it, but I must say it was a very specific set of conditions occurred for them to come into play.

Hmmm, I don't own that expansion but I'm finding it odd that they never seem to come up. Maybe I'm not playing with enough investigators or haven't triggered a particular story branch ? Or maybe they're only used with certain investigators playing ?

Without checking the card, can they be used in any scenario if an investigator goes insane? If it looks like they're trying to sabotage the investigation maybe you can use them on that investigator?

I could be wrong, I will check the card text later if it's one I have.