NEVER, RARELY, LITTLE, IN / UNDER NO CIRCUMSTANCES, ON NO CONDITION, IN NO WAY, NOT ONLY ... BUT ALSO etc.

When never, rarely, little etc. are placed at the beginning of the sentence for rhetorical effect, the subject and auxiliary are inverted:

Never (before) have we faced such a challenge! (We have never faced such a challenge!)

Rarely has there been so much speculation about the future of the company. (There has rarely been so much speculation about the future of the company.)

Little did she understand what the conversation was about. (She didn't really understand what the conversation was about.)

Under no circumstances are you allowed to disturb the pilots. (You are not allowed to disturb the pilots under any circumstances.)

On no condition will the company bear responsibility for lost property. (The company will not bear responsibility for lost property on any condition.)

In no way am I related to the suspect. (I am in no way related to the suspect.)

Not only did he exceed the speed limit, but he had also consumed alcohol. (He not only exceeded the speed limit, but he had also consumed alcohol.)

Not only were you late, but you didn't even have a good excuse. (You were not only late, but you didn't have a good excuse either.)