Script (guión): Idioms, ‘bad blood’. If people hate each other because of something that happened in the past, we say there is bad blood between them. There are two brothers who go to my local pub and there is bad blood between them as they had an argument over a woman many years ago. And they have been both coming into the pub and sitting on either end of the bar and never talking to each other. However, yesterday they spoke for the first time. I'm not going to tell you what they said, I'll save that for the next week.