go off the deep end 仓促行事；贸然行事；突然发脾气；勃然大怒；突然发脾气

【例句】
The bad news caused Jim to go off the deep end.
那个坏消息使吉姆勃然大怒,失去理智。

A friend of mine was about to go off the deep end when he felt he needed to talk to me.
我有个朋友在他脾气快要爆发时，觉得需要找我谈谈。