[General] How to get into an evil genius's bunker

Alright, so here's the Scenario.

This is a classic case of some Evil Genius freak who has made his own self sustaining and completely independent bunker deep underground At any location you can imagine.
Let's assume he shuts himself down with all of his friends/family/pets, whatever...
This means, there is no one who can get in or out of the bunker.
Let's assume the bunker is heavily fortified and heavily armed, there's no way to get anywhere close without getting killed in gruesome ways.

It is so deep underground even a nuke wouldn't scratch it, and it is designed in multiple layers so you can't just breach into it, you need to go through each of them.

So far his only crimes would be tax evasions and likely first degree murder and assaults on federal agents whenever they get close.

The question then becomes, how can you get to him?
What would it take to get him out of there dead or alive?