The veteran Rangers, having held back Thrax's forces, enlist the aid of an old ally to repair the damaged Morphing Grid, but the crestfallen and humiliated OO Rangers decide to return to their normal, civilian lives.

Thrax soon resurfaces much stronger, and his armada unleashes terrors the older team cannot combat alone, Mack must recover a powerful sword before the previous generations fall to a terrifying future shaped by Thrax's dominion...