And, yes. It is rather fascinating, and involves a bit of time travel as well. Because it's September 2014. And, interdimensional travel. Because we're in a world where SHIELD and HYDRA never existed. Well, only in comic books and movies, but I'll get to that later
And, believe it or not. It's actually magic that did it. A seal on the devil's cage, if I remember what I've been told correctly. It takes people from different universes, and times and brings them here. And then, one day it send us back to the exact point we left, and we don't remember we left.