English▸ noun
2 used to refer to a bizarre, confusing, or nonsensical situation or environment, typically one from which it is difficult to extricate oneself:
he'll continue fearmongering to promote his agenda no matter how far down the rabbit hole it takes him.
[with allusion to Lewis Carroll's Alice's Adventures in Wonderland (1865), which describes how Alice enters a land of magic and strange logic by falling down a rabbit hole]