A shipment of cardboard packaging hides a deadly secret. Heroin disguised as a computer laptop baffles the world's most advanced narcotic detection device. The diligence of agriculture specialists pays off and saves America's forestry from a potentially devastating insect infestation.

Officers are on high alert for a cartel ambush as they transfer a Sicario over one of the 28 border bridges and into the custody of the Mexico military. A random inspection of a pick up truck reveals 32 kilogrammes of narcotics while a man, his aluminium shed. A broken key brings chaos then smiles to the Gateway to the Americas Bridge in Laredo.

Officers are suspicious when an elderly couple arrive from Mexico with five suitcases but no clothes. On the World Trade Bridge, an X ray of a truck hauling garden furniture reveals something more might be in the load and in Laredo, officers help a woman and her child fleeing cartel violence in Central America.

Officers in Brownsville process an American citizen who crossed over the bridge 20 years ago and discover the reason he didn t want to come back. In Laredo, a car being driven by a man who claims he was coming into the country to shop at the supermarket, in fact, smuggling 15kg of cocaine while a truck driver s modified cab attracts the attention of Customs and Border Protection at the World Trade Bridge.

Officers become suspicious when they pull over a businessman from Mexico who is making a rare journey to the United States in a brand new car. On the Juarez Lincoln International Bridge in Laredo a man is detained after a canine alerts to drugs in a car. But why is he carrying such a small amount? Is it because he is a decoy for a cartel and trying to draw attention away from a bigger shipment of narcotics crossing the bridge at the same time? And an innocent pedestrian gets more than he bargains for when he is mistaken for a wanted man who officers believe is armed and dangerous.

Vigilant Customs and Border Protection officers uncover 5,000 rounds of ammunition being smuggled across Hidalgo Bridge into Mexico while 200 miles away in Laredo, an elite team prepares for the extradition of a hitman wanted for murder in his home country.

America's Gatekeepers are stunned when they discover over 2 million of the drug mixed in with gallons of household paint and bottles of beer. On the Gateway to the Americas Bridge in Laredo, Texas, a teenager from the Dominican Republic who has travelled 2,000 miles to the United States border in the back of a truck pleads his case for asylum while a man wanted on a warrant is found to be carrying something suspicious in the panels of his car?

In Hidalgo, a young woman from Cuba crosses the bridge in the hope of being granted political asylum in America while officers in Laredo get a surprise when they stop three biology students carrying something unusual in the boot of their car. Meanwhile, a new recruit is responsible for one of the biggest drug busts the Juarez Lincoln Bridge has ever witnessed.

Customs and Border Protection officers think they have spotted a trend when they seize drugs from behind the dashboards of two cars. One load has an ominous symbol that suggests it is the deadly new drug, Fentanyl, that is being concealed. Meanwhile in Laredo a Mexican woman and her children ask officers for protection from her eldest son a recent recruit to the notorious Los Zetas cartel who is threatening to kill his entire family.

A new recruit fresh out of training school makes her mark when she uncovers 12 kilos of cocaine hidden in a car. Officers on the border bridges are put on high alert for a kidnapped child who police fear has been smuggled over the border into Mexico.