We decided that a "muck" is a variable measurement, being the distance between Sharif and his car at any given time. So it's a phrase of very limited usefulness, but I like it anyway.
"Sharif realized he was late, so he ran amuck and sped away."
"Joanna borrowed Sharif's keys, ran amuck, and retrieved her jacket. She then ran amuck and returned the keys to their owner."