Twenty-five years ago, a missile silo south of Tucson was one of the most top-secret places in America. At the height of the Cold War, it was part of a network of nuclear warheads designed to avert a nuclear attack. The silo housed the Titan 2 Missile, which could be launched in less than a minute from its position 150 feet beneath the Sonoran Desert.

The missile was never launched. And the site is now a National Historic Landmark that hosts a museum dedicated to the Titan 2 Missile.

Yvonne Morris led a crew in the 1980s that was trained to respond to launch orders that they hoped would never come...Morris is now the director of the museum where the Titan 2 still rests in its silo. It's the last of 54 such missiles that were clustered in Arizona, Arkansas and Kansas. The rest have been destroyed. The Command Post deep inside the ground is like something from a sci-fi movie. Mint green metal panels are full of blinking lights, large switches, dials, and meters...