National Geographic Video: Secrets of the Titanic (1987)

Dr. Robert Ballard of Woods Hole Oceanographic Institute and his research team become the first undersea explorers to locate, photograph, and explore the wreckage of the ill-fated RMS Titanic, which sank on her maiden voyage 2 1/2 miles deep in the icy waters of the Atlantic Ocean in 1912, taking 1500 passengers and crew with her to a watery grave. Utilizing dazzling state-of-the art equipment and cutting edge expertise, they record the decaying remains of the ocean liner once thought "unsinkable".