Cardboard packaging hides a secret; a laptop bag conceals narcotics.

A cartel hitman is extradited, and 50 gallons of moonshine is intercepted.

A couple from Mexico arrives with candy unfit for children's consumption.

A new officer makes one of the biggest drug busts her bridge has ever seen.

Officers see a trend of narcotics being smuggled inside car dashboards. A teenager's tattoos send up red flags. A surprising load is found in a train car. A teenager attempting to cross the border is flagged as having an outstanding arrest warrant.

An officer catches a woman trying to use a forged visa to get into the US; a rookie officer takes part in a major cocaine seizure; officers suspect a traveller claiming to be a pastor on the way to a religious conference may not be who he says he is.

K9s save the day, identifying gallons of paint and beer bottles filled with more than the officers bargained for; a man with a warrant for his arrest is concealing something suspicious; officers question the intentions of a chatty traveler.

An elite team prepares for the extradition of a cartel Sicario, or hit man wanted for murder in his home country; with the sale of guns and ammo strictly controlled in Mexico, cartels turn to America for the weapons to wage their wars.

A traveller gets more than he bargains for when he is mistaken for a wanted man. Agriculture specialists deal with a shipment of cattle arriving without the required seal. Officers are suspicious when a businessman arrives in a brand-new car.

When night falls, a different type of traveller crosses the border -- and cartel spotters are nearby watching. A truck driver's modified cab is carrying a secret commodity. Officers find a surprise in a car that has never crossed the border before.