It's everyone's fear when they're gossiping in the cafeteria that the person they're talking about will suddenly pop up.
BBC reporter Nick Eardley was giving a walk-and-talk report on the upcoming election in the United Kingdom, and was covering slim chances for Scottish First Minister Nicola Sturgeon's party when he got tapped on the shoulder by a surprise guest.
Sturgeon cheerfully put her arm around Eardley's shoulder and he responded with a very surprised, very British, "Hello!"
This brought back memories for many.
People applauded Sturgeon's smooth move.
This instance ended well, but it's a good lesson.
Watch your back: You never know who's right behind you.