In the series finale, all factions clash violently in order to determine which path the future will take. While Kiera and Alec risk everything to stop the future soldiers and their devastating plan, Kellog, despite a loose alliance with Kiera, has plans of his own.
Kiera has serious trust issues with Brad when he seems more in step with the future soldiers than with her; Carlos and Kellog come to their own realizations about alliances and deception; and a strange encounter forces Alec to reflect on his destiny.
Alec takes a definitive step toward shaping a positive future by joining Carlos and the VPD. Meanwhile, Kiera's continued trust in Brad leads her to form an alliance with Garza in order to recon the new future soldiers compound and uncover their plan.
Kellog leverages Alec by exploiting his weakness, which, of course, is Emily. As Kiera attempts to negotiate with him unaware that Liber8 have other, darker plans, Alec grows tired of feeling helpless and impulsively sets off to save Emily by himself.
Season 4 begins with newly arrived time travelers threatening to destroy Kiera and her alliance with Brad. As she deals with the risk that they pose, she also finds herself yearning to return to her own time and her son.