The Apocalypse Troll

There Captain Richard Aston was, minding his own business as he single-handed his sailboat across the Atlantic while his Navy retirement was processed, when everything went to hell in a handcart.
First, there were the UFOs that decided to overfly a USN carrier group at Mach 17. Their impossible aerobatics were bad enough, but then they started shooting at each other. And at the Navy. With nukes....
Then there was the megaton-range upper atmosphere explosion that fried every bit of electronic gear in a radius of, oh, several hundred miles.
And after that, there was the very attractive, very young, critically wounded female alien he pulled out of the ocean after she baled out of her stricken spacecraft. Only she wasn't an alien, or as young as she looked. What she was turned out to be a tough-as-nails warrior locked in a duel to the death with an alien cyborg killing machine from a tech base hundreds of years in the future which would stop at nothing - literally - to kill her.
No one could really blame Richard Aston for thinking he was looking at a bad situation when his guest's explanation reached that point, only he was wrong.
He hadn't seen bad yet.
But it was coming.