Volcanologists search for data in fields of molten rock.
The 5th U.S. Special Forces Group establishes the Military Assistance Command Vietnam Recondo School.
Navy SEALs, Green Berets and Army Rangers help to win Desert Storm.
The Long Range Reconnaissance Patrols spy on the enemy in his own back yard.
The Mobile Strike Force functions as a roving SWAT team during the Vietnam War.
World War II glider pilots breach German defenses.
Sandhogs drive tunnels through solid rock and sinking mud.
The U.S. Army's 10th Mountain Division helps to win the war in Italy.
The dangers of space flight.
Hermann Goering's well-trained fliers rain terror upon Europe's great capitals.
Ice-breaking ships plow headlong into one of nature's most formidable barriers.
Hostage negotiators fight for the lives of the innocent.
The bloodiest battle in U.S. Marine Corps history goes on for 36 days.
The green beret of the British Commando becomes a symbol for the toughest, smartest and bravest soldiers.
U.S. Navy Seabees build and fight.
Special weapons and tactics originates in the mid-1960s.
Vietnam War forward-air controllers direct jet bombers toward target.
Merrill's Marauders fight the Japanese in Burma without tank or heavy artillery support.
Soldiers train to join the ranks of America's elite commando force.
The Rescue Swimmers of the U.S. Coast Guard and Navy save people from raging waters.
The law-enforcement division of the Fish and Wildlife Service is a small but dedicated group.
Specially trained soldiers and sailors are given secret, dangerous missions at the vanguard of the D-Day assault.
Long-haul truckers drive rigs over hundreds of miles of frozen Canadian lakes.
Classified covert operations of the Vietnam War.
Army Rangers use quick-strike tactics and an unshakable esprit de corps to brave withering fire and seize vital targets.
Combat medics perform one of the most dangerous jobs in war.
World War II German submarines held a stranglehold on Allied shipping in the Atlantic until the development of sonar.
Mining was once the most dangerous profession.
Daring enthusiasts track harrowing storms and witness conditions first-hand.
High-steel ironworkers raise skyscrapers and bridges.
The international community organizes special teams designed to confront and defeat terrorists on any playing field.
The military police protect justice in both war and peace.
Fearless airmen man B-17s' belly guns.
Fighter pilots destroy enemy radar and missile sites.
How the Pathfinders factored into D-Day and other battles of World War II, including North Africa and the Battle of the Bulge.
Silent assassins can kill with a single shot from miles away.
Lumbermen make the building of the nation possible.
Linemen erect, string and repair electrical transmission towers.
Infantry soldiers whose job it was to search for, find and destroy a subterranean network of enemy tunnels in Vietnam.
The Bureau of Alcohol, Tobacco and Firearms is charged with enforcing some of the most politically volatile laws in U.S. history.
The U.S. Navy's deep sea divers experiment with extremes of depth and time.
Detecting and neutralizing landmines carries a high price.
Forward observers gather information on enemy position and strength.
The First Special Service Force is one of the best-kept Allied secrets of World War II.
People place themselves in harm's way by working with earth's most fearsome creatures.
American tanks battle with Nazi panzers.
The U.S. Marine Raiders help to destroy Japanese supremacy.