On a mission funded by National Geographic, explorer-in-residence Dr. Robert Ballard researches the famed ''Unsinkable'' Titanic. He reveals details of its discovery and provides answers to some of its greatest mysteries.

Titanic's Nuclear Secret - In 1985, National Geographic Explorer in Residence Dr. Robert Ballard solved one of the greatest nautical mysteries of the 20th century when, while on a top secret naval assignment, he found the final resting place of the RMS Titanic. Now join the legendary explorer as he reveals the details behind this story of stealth, subs and superpowers as if taken from the pages of a Cold War spy thriller.

Secrets of the Titanic - This National Geographic exclusive highlights the century's most celebrated underwater expedition. Armed with sophisticated equipment, including the submersible deep-sea-craft ''Alvin'' and a myriad of remote video cameras, Dr. Ballard and his team became the first humans to see and photograph the Titanic since its sinking more than 70 years ago. Now the breathtaking footage of this exploration, as well as the intriguing story of the ship's discovery, is presented in its entirety.

Seconds from Disaster: Titanic - For a hundred years many have been perplexed by the details of what actually made the Titanic sink. Using a groundbreaking experiment that mimics the conditions of the Titanic as it scraped the iceberg, experts find new evidence that enables them to finally conclude what brought the ''unsinkable'' ship down in the middle of the icy Atlantic. Seconds from Disaster: Titanic includes haunting commentary of eyewitness accounts, CGI and cutting-edge experiments that help bring the Titanic back to life to retrace its final moments.