CNN National Correspondent Randi Kaye investigates this story that has rapidly captured the world's attention. On June 18, 2023, five passengers on the Titan submersible dived 13,000 feet to view the Titanic on the ocean floor and perished in a "catastrophic implosion," authorities said Thursday, June 22. This bookended an astounding five-day international search operation near the site of the world's most famous shipwreck. Kaye unravels the timeline of events, starting with the Titan's initial descent and their last communication to the surface. As investigators continue to scour the ocean floor for debris trying to establish the circumstances of the Titan's fatal final voyage, Kaye breaks down everything we know now.