A group of suspected drug smugglers is tracked by the all-terrain vehicle (ATV) night unit at Rio Grande City Station. No sooner are they apprehended than the agents must call in reinforcements from the CBP's air unit, Omaha, to track down a group of illegal immigrants hiding in the brush. Another team of agents searches for nine people missing in the Rio Grande, initially finding only one body. The search becomes more urgent when they find two more bodies the next day.