A long time ago in a galaxy not so far, far away, the National Cathedral gained an unusual sculpture: a carving of Darth Vader to adorn its northwest tower. As it turned out, Darth Vader, the result of a design competition for children, is a very fitting figure for the Cathedral's decoration.

For decades, the land on the western bank of the Potomac River that is currently home to the Pentagon, Ronald Reagan National Airport, Roache’s Run Bird Sanctuary, and part of the George Washington Memorial Parkway was disputed territory. Did it belong to Virginia? The District? No one seemed quite sure.

Although the Capitol has withstood plenty of attacks from foreign and domestic adversaries over the years, sometimes the most destructive forces can come from something as common as a gas leak... How did a series of accidents and events lead to one of the most devastating incidents in the Capitol's history? What priceless artifacts were lost forever, and who were the people risking their lives to prevent further destruction of the nation's history?

A guard patrolling the basement of the Capitol during the Civil War is attacked -- not by enemy soldiers, but by a giant, demonic cat! Over a hundred years later, the "Demon Cat" is still one of Washington's greatest ghost stories, which is saying something in a city with as many phantom residents as the capital. What is the real story of this mystical mouser?

On a cold, overcast Tuesday morning in February 1981, something caught the eye of a museum technician as he walked through the “We the People” exhibit on the second floor of the Smithsonian National Museum of American History: The silver pen of President McKinley’s Secretary of State John Hay was missing. The 7 ¼-inch Parker Jointless pen had been used to sign the 1898 Treaty of Paris, ending the Spanish-American War.

But now, to the technician’s horror, its case was empty -- and there were more alarming discoveries to come.

While digging a sewer near the Capitol in 1898, a construction crew makes an incredible discovery- a fossil! Only, when it's brought to the Smithsonian, no one is able to say for certain what kind of dinosaur it might belong to. Could this be a clue to a dinosaur found only in the District? See how generations of paleontologists dispute the identity D.C.'s oldest resident, and how a group of school kids played a factor in solidifying its legacy.