The sides have been established on Heroes.

This Monday, a war is officially brewing. Various characters are dispatched to remote parts of the world, with one goal in mind: stop the enemy... before it's too late!

Check out the official NBC preview for the episode, which is mysteriously titled "The Eclipse Part 1."

[video url="/videos/a-promo-for-the-eclipse/" title="A Promo for The Eclipse"] [/video]

Matt Richenthal is the Editor in Chief of TV Fanatic. Follow him on Twitter and on Google+.