Every day thousands of men, women, and children attempt to enter the United States illegally—some looking for work, some seeking a new life, and others trying to smuggle drugs or other contraband. Many will do whatever it takes, often risking their lives by crossing treacherous terrain. Now, follow the officers and agents of U.S. Customs and Border Protection (CBP) as they scour the inhospitable landscape at one of the busiest border crossings in the country, seeking to fight terrorism and intercept illegal entrants from the air, on the ground, and at the ports of entry.