A malevolence lurks outside your bunker. Fathomless, omnipotent, and deadly, it devours the world with each passing day.
The three of you swore to kill it--no matter the cost. Even if it means you've got to nuke everything. Ordinary (good) people won't do it. They can't fathom the horror.
Evil acts out of necessity. Villains know what must be done.
Yet your leader's having second thoughts. She's getting cold feet; and if the two of you can't convince her to use the weapon, then maybe it's time to take matters into your own hands.
Are you ready to save the world?