Here's what it's about. A new Inhuman named Ulysses has visions of the future. Captain Marvel has seized upon this opportunity to advocate for new laws that allow SHIELD and Earth's superheroes to arrest people for pre-crimes.
So Ulysses tells everyone that Hulk will kill everyone. They all confront Bruce Banner -- who's been Hulk-free for months -- and Hawkeye ends up shooting Banner in the head. He claims that his trained eye picked up a bit of green and he knew that he had to act. Not that Spider-Man's spidey-sense picked up any danger.
Hawkeye walked and now Captain Marvel and SHIELD are going crazy with pre-crime arrests. This leads to a huge battle between the Captain Marvel (alongside the Ultimates, Alpha Flight, the Extraordinary X-Men, and the Guardians of the Galaxy) versus Iron Man (alongside the All-New Avengers, the All-New X-Men, Old Man Logan, Doctor Strange, Captain America, and the other Captain America).
I won't reveal the big spoiler (though it's hardly a spoiler anymore), but there was one development that promises to affect the Guardians of the Galaxy for the foreseeable future. Vision blew up their starship and effectively stranded the team on Earth.
That's right. Fans of the Guardians of the Galaxy will be treated to several months of Star-Lord, Rocket Raccoon, Gamora, Drax, Angela, and Groot complaining about that backwoods planet called Earth. However will they cope?
It's too bad that they don't have a starship anymore or access to anyone who could get them to astarship or a place where they make starships!