What did the world look like as it was transforming into the horrifying apocalypse depicted in "The Walking Dead"? This spin-off set in Los Angeles, following new characters as they face the beginning of the end of the world, will answer that question.

Colombian drug kingpin Jesús Morales secretly pays for the services of a sniper nicknamed "The Devil," capable of killing one-by-one the enemies of anyone who hires him. With no adversaries left alive, Morales grows stronger and gains control of more smuggling routes into the United States. The DEA, alarmed by this threat to the country, sends agent Kate Estrada, who has been following Morales for years, and Marine sniper Brandon Beckett to Colombia. Their mission: Kill "The Devil" and bring Morales back to the US to be tried for his crimes. The agents think they have everything under control, but Morales and "The Devil" have prepared plenty of surprises to keep the mission from succeeding.