The first thing that came into my mind was an incident that happened a few years back.

And friend and I walked down a quite street that had many apartment buildings. Suddenly in one building, just at the entrance, there was a weird fight happening. One man stole the luggage from another man. They did not yell at each other, they did not hurt each other. They were only fighting for that black luggage. As soon as the thief was successful, he fled with the suitcase into a car and drove away. We asked the other man if he needs our help as witnesses and if we should call the police. But he kept weirdly calm about it. He said he knows the thief.

I still wonder, what was in that suitcase and how this weird situation played out from the beginning.