I can understand why certain people go off the deep end.
I think he was right to go off the deep end.
I've not gone off the deep end as you think the rest of them have.
He is not likely ever to go off the deep end.
Had he really gone that far off the deep end?
That was being put in the deep end for a start!
You don't have to go off the deep end and start taking drugs to be different.
No one knows what set her off the deep end about this case.
Are we to think that he's gone off the deep end?
"This is a fine time for him to go off the deep end."