Everything in the Arrowverse is about to change forever.

Crisis on Infinite Earths, the five-show crossover uniting Supergirl, Batwoman, The Flash, Arrow, Legends of Tomorrow, Black Lightning, and about a thousand other DC superhero properties, premieres this Sunday, and at least based on what we've seen, it's unlike anything that's happened on TV before.

Basically, an alien being called the Anti-Monitor is threatening to destroy (as in, completely and totally erase from existence) entire worlds. Earth-2 and many others are already gone, but there's a chance to stop the destruction by uniting heroes from all over the multi-verse. Sacrifices will be made, people will die, and things are gonna be a little different when the smoke clears in January.