 American bombers assemble at a secret airdrome, somewhere along the northern tip of Australia. The order of the day, attack. General Royce and General Scanlon in command. One by one, the huge ships take off. Weeks of planning, months of training, now put to the test. As pursuit planes roar down the strip and zoom aloft at incredible speed. These are the fighters of the air fleet. Daily they go up and daily they land. From the looks of the bullet holes, some of them have made contact with the enemy. Battle scars that show that American ships are built to take plenty of punishment. Credited with staving off the invasion of Australia, these young pilots know their business. Here's one coming in now. His landing gear jammed by Japanese bullets. He's forced to make a crash landing. Dangerous with any ship, doubly so with a bomber. Has a perfect job. All hands aboard safe and sound. The pilot is congratulated by the general and mentioned in official dispatches. Only a few repairs are necessary and the ship will soon be ready to fly again. A thrilling example of how American airmen are rapidly winning the mastery of the skies. There's army nurses who served under fire in the Philippines. Heroines of Manila, of Bata and Corregidor. Their deeds have written an epic chapter in US history. Mrs. Roosevelt looks on as six who came back receive medals for valor. To student nurses, their courage is an inspiration. Caring for the wounded until told to go, they were the last to leave. On the home front, women enlist for less glamorous, less hazardous, but equally important work in industry. Replacing men who are called to the colors, these girls are operating one of the nation's biggest lumber mills. Today, women in overalls, women in war jobs are to be found throughout the length and breadth of America. Even at army proving grounds, the so-called weaker sex is doing a man-sized job. Testing tanks is just daily routine for this all-girl crew. The latest machine guns, 50-millimeter aerial defense weapon with plenty of kicks. They feed shells and fire them with clockwork precision. Arsenal's of the steel makers, the heart of industrial America, providing the United Nations with the tools of war. Here in the giant furnaces of Chicago, of Detroit, Cleveland, Buffalo, Pittsburgh, America is producing more steel than the rest of the world combined. Now geared solely for the production of steel for war, the mills are rolling 24 hours a day, seven days every week. Endless streams, the hot molten lava flows to the forge of Mars. Out on the Great Lakes and to the mountain ranges beyond, mammoth carriers race to keep up with the mill's demand for iron ore. In the largest open-pit iron mine in the world, the battle of transportation begins. Digging a man-made canyon a mile wide and two and a half miles long with electric shovels weighing three quarters of a million pounds, shovels that take 16 tons of ore in each scoop, loading a 50-ton railway car in three mighty bites. Day and night, 85 car trains roll down to the ore docks. Each train carrying eight and a half million pounds of iron ore in every load. Below the massive trestle, ore bends jauning wide, the lake freighters await their cargoes. The big chutes open and down it pours. Record loading time, 13,000 tons in 16 minutes, enough ore in a single cargo to build six modern destroyers. Out into the broad waters of Lake Superior, the carriers begin to move. A bridge of ships of 1,000 miles long, 20,000 passages a year, racing against time and the weather. The race begins with the first cold days of the northern spring. For in eight months, the freighters must haul enough ore to keep the steel mills working through the entire year. Through the peril of fog and snow and ice, across 90,000 square miles of landlocked water, the Great Lakes Fleet is winning the battle of transportation. Iron ships and iron men supplying the sinews of war to the arsenals of democracy, the mills of America's steel makers. Tennis fans the world over hail Donald Budge and Bobby Riggs as two of the greatest exponents of the game. At Long Island's famous Forest Hills, the Wimbledon of America, they meet for the national professional championship. Budge serving, 26 years old, Don holds more titles than any man in tennis. And he's winning again. Europe remembers the Yankee redhead for his brilliant performances with the Davis Cup team. Riggs serving, and today he's no match for the champion. Serving in the far court, and this time Riggs wins a point. But Budge has two sets, and he's taking the title with three in a row, undisputed master of the courts. 70 tons of airplane. The US Navy's new $2.5 million experimental flying boat, Mars, now ready for her maiden flight. Capable of flying the Atlantic and back without stopping for fuel, the mighty Mars is a forerunner of things to come. Contrast between a Navy patrol bomber and the giant amphibian is striking. Four monster motors, each with more power than a locomotive. Armed to the teeth, planes like the Mars can speed men and weapons to the battle fronts of the world in a matter of hours. Canada's answer to Nazi U-boat sinkings. First films of the Dominion's fast new fleet of submarine chasers in action. Picking up a convoy, they test their new anti-submarine gun. For terrific speeds, they cut the water like a knife. Equipped with powerful depth charges carrying higher explosive power, they can blow up or cripple a lurking U-boat in more than twice the area possible a few months ago. Here's a sample. And in 30 seconds, another's ready to go over the side.