beyond the pale
If someone's behaviour is beyond the pale, it is unacceptable:
Her recent conduct is beyond the pale.

[TahlilGaran] Advanced Learner's Dictionary ▲

beyond the pale
not acceptable to most people.
For most people, a discussion like this has been simply beyond the pale.

Etymology: based on a past meaning of pale (= an area in Ireland, Scotland, or France controlled by England), and the idea that places outside this area were dangerous for the English

[TahlilGaran] English Idioms Dictionary ▲

beyond the pale
to be outside the bounds of acceptable behavior
What they are doing is totally unacceptable and beyond the pale.

[TahlilGaran] English Idioms Dictionary ▲

beyond the pale
adv. or adj. phr. In disgrace; with no chance of being accepted or respected by others; not approved by the members of a group.
After the outlaw killed a man he was beyond the pale and not even his old friends would talk to him.
Tom's swearing is beyond the pale; no one invites him to dinner any more.

[TahlilGaran] English Idioms Dictionary ▲