Now Playing: Instant Index: The Titanic's Haunting Fate Possibly Revealed in a Prophetic New Clue

Now Playing: San Diego Police Release Video of Alfred Olango Shooting

Now Playing: East Coast Braces for Severe Weather

Now Playing: Trump Goes on Early Morning Twitter Attack

Now Playing: Trump Gives Deposition in Celebrity Chef Lawsuit

Now Playing: More Details Emerge in Hoboken Train Accident

Now Playing: Cause of Death Released in Sisters Mysterious Death in Paradise

Now Playing: Rosetta Spacecraft Ends 12-Year Mission

Now Playing: Selfless Volunteers Searching for Survivors in War-Torn Syria

Now Playing: NJ Train Crashes in Hoboken Station During Rush Hour

Now Playing: Nearly a Quarter of Young Voters Favor Third-Party Candidates

Now Playing: Federal Investigators at Scene of NJ Train Crash Within Hours

Now Playing: Newly Released Body Cam Video Shows the Aftermath of the Deadly Police Shooting in Louisiana

Now Playing: Heroic Volunteer Firefighter Credited With Stopping SC School Shooting

Now Playing: Tropical Storm Matthew Now a Category 1 Hurricane

Now Playing: Donald Trump Takes Heat for His Performance in First Presidential Debate

Now Playing: New Developments in the California 'Gone Girl' Case

Now Playing: New Outrage Involving Wells Fargo Repossessing 100s of Cars Belonging to Active Service Members

Now Playing: Teenager Armed With Handgun Shoots at Teachers and Children on the Playground

Now Playing: Fresh Protests Over the Deadly Police Shooting of Alfred Olongo Near San Diego