ACT 1
Mike shouldn't even be alive. Foxy should've killed him when he had the chance. Now, they're roommates.
Mike begged to not be shoved into a Freddy Fazbear suit, and the animatronics agreed, on the condition that he lives at FFP. Now, he has to deal with Freddy constantly trying to kill him, his boss putting him in shows, and Chica flirting with him.
ACT 2
After saving the world, Mike must stop Purple Guy from killing the children. The Toys send him to 1987, where he teams up with Jeremy and Phone Guy.