In the tension-filled days leading up to the Civil War, the Rio Grande Valley is girding itself for battle. As sides are chosen, Martin Baron, head of the Baron family empire, struggles against a greedy rival rancher, Matteo Aguilar, who threatens everything that Martin has built for himself.

When Aguilar sends his vaqueros and assassins to take the Barons down, he starts a bloody war that won't stop until only one family, and one ranch, remains. As the treachery continues to escalate, the Barons find themselves in a life-or-death-struggle that will change their entire family forever.