Today's Trope: What if pizza was never invented? (a.k.a. parallel worlds). When characters visit another world that is similar to ours, but slightly different in a variety of ways, we’ve entered the realm of alternate universes! Whether every character has an evil twin, pizza was never invented, or everyone’s favourite superhero is the red lantern, parallel worlds offer opportunities to explore what if questions, have beloved characters die (but not really), and explore alter-egos.