Falling Skies' Espheni invaders will confront the 2nd Mass with a whole host of new baddies when the series returns to TNT for it's fourth season.

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Remember when Skitters and Mechs were the worst of humanities problems? Tom Mason (Noah Wyle) and his band of survivors will be looking back on those days wistfully after they get a deadly introduction to the aliens' latest inventions during "Ghost in the Machine."

"The Espehni engage a totally new form of warfare against us," Wyle warns in a season overview.

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This new approach includes a prison guarded by the 'Eye in the Sky.' A floating ship that hovers above the enemy's new internment site, the deadly 'Eye in the Sky' helps a fishhead named Scorch keep watch over human captives (see first video below).

Those earthlings who haven't been placed in prison or the new children's reform school have to worry about battling obelisks and black hornets. A flying form of Skitter, black hornets can now rain destruction from above while obelisks will be used to corral resistance fighters and zap them into oblivion (see second video below).

Can humanity overcome the Espheni's latest onslaught, or will they severely regret refusing to accept the Volm's Brazilian relocation camp? Find out when Falling Skies returns to TNT on June 23.