The issue begins with Sam pondering his recent encounter with the Hulk during the Original Sin event, in which he was struck so hard that he got a major concussion. His career as Nova was briefly put on hiatus and now he was visiting the last person he had hoped to see – The Hulk, now going by the name of Doc Green. The Doc Green personality is neither Bruce Banner, nor the Hulk, but a separate personality that developed after the attempted assassination of Bruce Banner.
When Nova sees him, he reacts initially by blasting Doc Green, mistaking him for the savage Hulk who had caused him the major concussion. Doc Green apologizes for his actions as the Hulk and explains that he was not himself at the time. Alex explains that he was there looking for Mister Fantastic, hoping he could fix his helmet. Doc Green explains he’s not there, and they both mutually agree that Tony Stark is too much of an arrogant jerk to ask for help. Doc Green offers to see if he can help repair Nova’s damaged helmet.
Not wanting to reveal his true identity to Doc Green, Alex is forced to wear a paper bag over his head with the eyes cut out so that Doc Green can examine his helmet. Doc Green finally comes to the conclusion that there is nothing on Earth that can fix the helmet. When Alex seems distraught by the news, Doc Green explains that nothing on Earth can fix it – but that it can be fixed, there was just nothing on Earth that had the components he needed. Nova says that he knows of a place that he can get spare parts in space, but can’t fly out there without his Nova helmet. After a great amount of convincing, Doc Green agrees to fly one of the Fantastic Four’s spaceship into space. They arrive at the Nova bunker where there are several helmets of from the Black Nova Corps, but they’re all too damaged and none of the parts are there. Sam uses his helmet to show a space map of where the Fallen Black Nova Corps are, just the way he had used the helmet to originally find the fallen Nova Corp members. Doc Green explains he knows where to go and to grab the other Black Nova Corp Helmets.
Together they fly to Xandar, the home of the Nova Corps. On Xandar, they encounter Zarihs Didisiqui and his family of scavengers. Sam shows them his damaged Nova Corp Helmet, and they seem to reel back from the Black Nova Corp helmet, recognizing it immediately. They explain that an alien named Gron has enslaved people and forced them to work for him excavating artifacts from Xandar. Doc Green recognizes him a Darkkamite, which absorbs starlight to give him fantastic abilities. Doc Green grabs the Black Nova Corp helmet from Gron, and then uppercuts him, sending him into the sky. Doc Green explains that Gron will be fine, and that it’s probably a good idea to get off the planet before he makes landfall. While that was happening, Zarihs took his family and escaped in the spaceship that Doc Green and Nova had taken from the Fantastic Four.
Doc Green manages to fix Nova’s helmet. They leave Xandar by Nova grabbing Doc Green and flying him to Nowhere, the Celestial Head floating in space, managed by Cosmo, the Russian telepathic canine. Cosmo is able to teleport Doc Green home – putting him, per Nova’s request – in a volcano (which Doc Green had mentioned he survived before) – all to get “even” for what Doc Green had done as the Hulk to Nova.
Nova leaves Nowhere and gets the emergency broadcast – and it’s about something called the Black Vortex. Nova arrives and sees several members of the Guardians of the Galaxy, the X-Men, and others, fighting over what appears to be a mirror called The Black Vortex.
This leads into a limited series called Black Vortex Alpha, and continues the story in Nova #28.