Hitler Prime stroked his mustache, discretely removing evidence of a recent Egg McMuffin. “You see,” he explained to the temporal assassins, “time travel via your machine in the strictest sense is clearly impossible. But parallel worlds are possible. You did not actually travel to 1930 in your own world, you traveled to a parallel world in which 1930 happened to align to your 2041.” “But, we killed you!” stammered Biff.