Why was Falling Skies Earth invaded by the Espheni? Season 5 will give viewers the answers they have been waiting for.

'Falling Skies' Season 5: 'Time For Overkill,' Wondercon Clip Shows Tom Mason's Return

Drew Roy (Hal) dropped by WonderCon last Saturday and announced that the explanation behind the presence of aliens - and the reason they came to Earth in the first place - will be tied up with the new creature that intercepted Tom Mason's (Noah Wyle) ship in the season 4 finale.

"It does come to an end; we explain why they're (the aliens) here (and what) their motives (are)," Roy said at WonderCon, according to TV Equals. "[The] figure seen at the end (of "Shot the Moon") is the catalyst (who is) tied (to their) interactions."

'Falling Skies' Season 5 Premiere: 'Nothing Will Be As It Was', First Promo Released With Tom Mason

A clip from the Con shows a determined Tom reunited with remnants of the 2 nd Mass (see video below), more than a little determined to end this war once and for all. A press release for the final season indicates that he won't be the only human ready to see the backs of their fishhead overlords.

"As season five opens, all breed of beast and mutant are running rampant on earth," TNT teased. "The Espheni's power core has been destroyed, and humans are now ready to fight on their terms, even if it means resorting to hand-to-hand combat against the enemy. After four years of being tortured, imprisoned and mutated and having their loved ones stolen from them, Tom and the 2nd Mass are filled with rage, ready to destroy the enemy in an all-out battle to determine the fate of Earth."

Find out more when Falling Skies returns to TNT on June 28 at 10 p.m. ET.