Warning: contains spoilers for Guardians of the Galaxy Annual #1!
Nick Fury is officially taking over for Sam Wilson as the high-flying Falcon...but the promotion might not be entirely up to him. The director of SHIELD is offered the job in the back story to Guardians of the Galaxy Annual #1, Infinite Fury Part VI, written by Jed MacKay with art by Juan Ferreyra. But Fury isn't just filling in Falcon's shoes - he's been offered the job to be the partner of Nighthawk...from the Heroes Reborn universe.
The Heroes Reborn universe - a creation of Phil Coulson and the demon Mephisto, in which the Avengers were replaced by the Justice League-analogue Squadron Supreme - was destroyed by Blade and the re-assembled Avengers, but the fallout remains. More specifically, Nighthawk, essentially the Marvel Universe's version of Batman, escaped the authorities and sets out to recreate his disappeared world. Nighthawk, like Batman, stands for order over chaos...and like Batman, uses questionable methods to achieve his goals.
"He opened my mind to what was possible," Fury says of Nighthawk. He continues that Nighthawk told him of the "other" world, and it becomes clear to the reader that while Nighthawk remembers the events of Heroes Reborn, many other do not. So dedicated is Fury toward Nighthawk's cause, he even runs from the police after stealing an item from Project Pegasus that can track down the Infinity Stone hosts. After being asked to take on the mantle of Nighthawk's dead partner, Fury proudly stands in front of a mirror holding the Falcon suit...but something is amiss. Fury appears to say random unconnected words and can't control his speech: an "intervention trigger." Finally, he says "Mental shutdown initiated" as the issue draws to a close.
Something sinister is afoot; it becomes clear to the reader that Fury's unending praise of Nighthawk isn't of his own volition. Nighthawk has brainwashed him into doing his bidding; Fury's "intervention trigger" appears to be a contingency plan in case Fury's mind became compromised (an expected precaution considering Nick Fury is a historically paranoid person). Nighthawk clearly seeks to restore the Heroes Reborn universe and desires the Infinity Stones to do it. Nighthawk would arouse suspicion, but with Fury as his instrument, his goal is attainable.
The detailed aftermath of Heroes Reborn remains largely unknown. While characters like Hyperion wander aimlessly and Blur is captured by the police, Nighthawk remembers everything and remains the most dangerous member of the Squadron Supreme. Imagine Batman turning against the Justice League: though both him and Nighthawk are ordinary humans without any powers, their mind is what makes them truly formidable. Perhaps the only person more prepared for any eventuality than Nighthawk is his new, unwilling "partner", Nick Fury.