Frustrated with teaching and seeking a life of adventure, Albert Einstein builds a time machine intending to visit the 19th century and trade places with his natural doppelganger, Mark Twain. Unbeknownst to him, Nazi scientists have secretly been developing their own time travel plans with ambitions to conquer the world two generations earlier using an army of reanimated corpses from the first World War It's up to the world's greatest scientist to...