They refuse to accept the hard-and-fast rules that are laid down for them.
This is not a hard-and-fast rule, but one which usually it is safe to follow.
She taught me to dance against and around the hard-and-fast beat of the music.
A matter with which, by hard-and-fast agreement, she has absolutely nothing to do!
So I bound myself by a hard-and-fast contract so that I could ...