During a routine operation, Spanish police arrests the world's most wanted terrorist. This puts Spain in the crosshairs of jihadists. La Unidad, the unit which specialized in preventing and deactivating attacks, will have to work against the clock to avoid an attack.

The disappearance of an undercover agent, infiltrated into the terrorist cell, triggers all alarms. La Unidad investigates the surroundings of the detained terrorist leader to detect the connections and next steps of the terrorist cell that threatens Spain.