A major secret behind the Skitters' identities was revealed on Falling Skies this week, while viewers are gained insight into Weaver and finally met up with Karen again. In a disturbing manner.

How will these revelations affect the first season finale? It will air for two hours this Sunday and focus on the planned attack against the alien structure in downtown Boston. Look for Tom to struggle with Annie's discovery, and for the motives of the occupying forces to be revealed.

Check out the official TNT trailer for the finale now:

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