Humanity is approaching a critical moment in TNT's Falling Skies.

All season long the rebels of Charleston have been teaming up with the Volm in order to create a weapon powerful enough to take down the Espheni grid.

"We are approaching the epic climax of a long journey that began three years ago when the human race seemed to be on the run, just trying to survive," said writer David Weddle, according to Entertainment Weekly. "It's going to be the moment of truth for Tom (Noah Wyle). Victory isn't easy. Tom Mason will be tested to the max in the last episode. I think people will be surprised at some things that happen in the finale."

While the Volm appear to have been destroyed by the Espheni, a teaser shown at Comic-Con shows a large number of Volm confronting the rebels in a menacing manner.

In the meantime, the 2nd Mass. is dealing with a traitor among their ranks.

"All season long we've wondered who's the mole. To our amazement it was Lourdes," said director Greg Beeman, according to Entertainment Weekly. "Do we get rid of her or take her on the mission?"

As the rebels travel to Boston (Chicago, New York, or Jacksonville), the Entertainment Weekly's Unanswered Question Video shows Lourdes (Seychelle Gabriel) tied up on what appears to be a train as Hal (Drew Roy) tries to tell her he knows what she's going through.

The ultimate question still on fans minds, however, is the fate of Anne (Moon Bloodgood) and baby Lexi. While Karen (Jessey Schram) managed to convince Tom that his young daughter and girlfriend are dead, Weddle claims the aliens are very interested in the new race that is Lexi. Would they really kill her?

The season finale of Falling Skies airs Sunday at 10 p.m. on TNT.

Tags: falling skies