"I hate to bother you, but is this the residence where the beating is commencing?"

     Heh, different times different responses. Actually I generally go with, "Hey I heard a lot of noise, is everything all right over here?" You say this while staring straight at the guy. Ignore the frightened woman in the corner. It makes the point that your not going to run scared or back down. If they're sober then they typically realize that you can call the cops at will. Meaning they usually say they'll keep it down. This breaks the violence of the moment, a chance to cool down a little and gives him good reason not to continue. If they're drunk then they usually get belligerent.
     I had to intercede between a drunk would-be girlfriend beater and an ex-marine buddy of mine. Drunk nearly got himself maimed. The drunk deserved it, but I knew the chic. She'd have been upset about it. So I cooled things down for her sake.
     When a chic I'm friends with had a problem with her ex all I had to do was show up. I looked at him, he looked at me with the expression of, "Oh shit, I'm that guy." He left quickly without looking at me again.

     On the other hand, I've never had anyone get beligerent when they were stranded on the side of the road. I've had a few act nervous, but never beligerent. Usually, they're pretty appreciative.

One time, years ago, the young couple that lived in the apartment above me were making a hell of a racket. Sounded like murder. I went to their door not knowing what I was going to do. The woman answered the door. I managed to say "You OK?" She busted out laughing. Seems her husband, when he didn't get his way, would run around the apartment throwing himself into furniture and walls. I just retreated amazed and confused, but mostly grateful I didn't have to test my convictions.

[Phil]Your ways are frightening and confusing to me.[/Hartman]