BloodyMary AU: The One Where Simon Is In A Time Travel Fix-It (aka. The One Where Ryland Grace REALLY Fucked It Up)
Simon has vaguely heard the stories of the Hail Mary. Humanity's last ditch efforts to save the stars, which was ultimately fruitless. As far as humanity knows, the Hail Mary launched with three passengers, and then nothing. Radio silence. No beetles, no hope.
What happened in the Iron Lung universe was this:
Grace wakes up with dead crewmates, meets Rocky, and everything proceeds as canon, except Operation: Time Go Fishing. Rocky is too late in breaking the xenonite and the ship crashes on Adrian. No beetles are sent because everyone is dead.
What everyone in the Iron Lung universe THINKS happens is this:
Grace, the coward who was forced onto the ship that would save the world kicking and screaming, who openly declared that he would sabotage the mission. Well. Sabotaged the mission. He got everyone killed, the stars died, and basically, he doomed the human race. Everything now is Ryland Grace's fault, and his name is practically synonymous with Coward, Murderer, and Pretty Much The Devil because he Killed Everyone.
So, Simon ends up on the Hail Mary, but he doesn't show up on the trip to Erid like in many other fantastic fanfictions. He shows up right after GRACE wakes up. And when he realizes Grace doesn't know jack about shit, he lies, somehow shoots Yao out the airlock without Grace noticing, and convinces him that he, Simon NoLastName, is DEFINITELY the pilot on the Hail Mary.
From Simon's perspective, he's in a Time Travel Fix-It Fic. He is stuck on a spaceship with the devil incarnate, who Killed Everyone, and his job is to watch the guy like a hawk to make sure that he doesn't do that again. And also hopefully handle the whole alien thing, because that probably is related to the whole Killing Everyone that Simon is here to stop. In his mind, Grace is just faking this whole nice guy 'I have amnesia' nonsense until Simon puts his guard down and Grace can do whatever he did to get everyone killed last time.
From Rocky's perspective, he's in a Buddy Comedy, but he got TWO aliens instead of just one! And the science one already likes him and seems to understand a little bit of Eridian! Amaze amaze amaze!
Wait, but how does Grace already understand Rocky?
Because, from GRACE'S perspective? Here's the plot twist. Grace also time traveled.
He knows something is up with Simon. Obviously. He knows something fucking weird is happening. Obviously. He also knows he has one (1) goal, no matter what, over everything else. He doesn't have TIME to worry about Simon, or whatever is going on.
The ONLY priorities that Ryland Grace has is to Succeed at Operation: Time Go Fishing and Don't Let Rocky Die. And he's willing to go along with Simon's presence and pretend to still have amnesia to get there, because he NEEDS to get back to Operation: Time Go Fishing.
So the entire AU is Grace and Simon essentially doing the highest stakes improv that the universe has ever seen, neither of them trust each other, both of them think the other is going to murder them and is also super evil, and both of them are terrified of the other fucking them over and dooming the human race...
And Rocky thinks this is Normal Human Behavior, and rolls with it accordingly, which makes everything worse.