Plenty of snippets have given hints as to the crossover craziness in store for fans of The CW’s Arrowverse this year, with the Flash and Green Arrow swapping lives, the appearance of a few familiar (and unfamiliar) DC faces, and some definite mucking about in the alternate realities that are these shows’ bread and butter. Now, however, fans can get their first glimpse at the "Elseworlds" event’s primary plot, straight from the source.