Doc Brown found himself in Universal Studios Florida after flying across the sky in the DeLorean that he time traveled through when he suddenly noticed a bunch of Touhou girls popping up out of the void near him; given that this was 1990 he was at the spot that would eventually be the sight of the Back To The Future ride.

"Great Scott!" Doc Brown exclaimed in surprise with a stunned look on his face.

"Hey isn't that scientist dude the 1 from the movie we watched?' Reimu asked with her arms folded together.