Waiting to pay at the checkout of supermarket. In front of me, a man.
“Would you like a bag?” asks the cashier.
“No, thanks. I can manage.”
While paying he says to the cashier “Well, yes, actually. A bag please.” And she replies “That’s what I said at the beginning, that you’d need a bag. But don’t worry. I’ll help you.” And she proceeds to help him put the things in the bag.
And there we have, in less than 30 seconds, the three roles in the Karpmann triangle: the Victim (or at least that’s what the cashier perceived, the Perpetrator and the Saviour.
And the speed with which you can move from one to the other.