Most scientists believe that you are not really you, but rather, you all. On the edge of space, buried in a black hole, or right on top of you, there could be an exact copy of yourself living a parallel reality. In those parallel worlds, you may be living your wildest dreams, or your worst nightmares. Finding them is no longer restricted to the realm of science fiction. Recent game-changing theories now suggest that if these worlds exist, intelligent life in these alternative worlds could be trying to send us messages. As scientists further unravel this astounding possibility, a new possibility emerges: the fate of our entire universe may depend on these hidden cosmic twins.