If you get a call from an unknown number, and they don't leave a message, and you've missed the call.
1. Who do you first assume called you?
2. Why would they call you from the unknown number?
This can either be from an actual experience, or, a story you've made up in your imagination.
I haven't thought this through very much, but I always assume it's one friend in particular, who got into trouble and is using their only phone call from the precinct. I might use my friday night to make this into a story