The Falling Skies will battle the Espheni for a final time in season 5, and the cast of the 2nd Mass returned to set for their last round of filming on Tuesday.

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When season 4 wrapped up, Lexi was dead, the moon's power core was destroyed, Tom was lost in space, and the resistance fighters managed to survive an onslaught of human skitterization bugs. Now, humanity must complete the final leg of their war against their otherworldly invaders.

"Wakey-wakey for a 4:30am pick-up! ... Ugh. Cameras begin rolling today for our final season 5 of @fallingskiestnt !!!" tweeted actor Doug Jones (Cochise) as he headed to set to film with Colin Cunningham (Pope), Connor Jessup (Ben), Mira Sorvino (Sara), and Treva Etienne (Dingaan).

Lourdes' 'Super Awesome' 'Falling Skies' Death Explained, Seychelle Gabriel Talks Leaving The 2nd Mass

While the character's mentioned above have already began filming for the premiere, the rest of the Mason clan and Maggie (Sara Carter) won't begin shooting until later in the week. That doesn't mean the actors haven't been busy, however.

"No more sitting around the house watching Netflix anymore. It's time to #FakeSaveTheWorld," tweeted Drew Roy (Hal) on Sept. 10 when he headed back to set for gun training ahead of production.

Find out what's next for the Masons and the 2 nd Mass when Falling Skies returns to TNT next summer. Click the video below to see a preview for the series' latest episode.