A search for answers is underway after the missing OceanGate submersible suffered a "catastrophic implosion." Meanwhile, the US Navy says it detected the sound of a possible implosion on Sunday around the same time communication was lost with the vessel. Filmmaker James Cameron, who directed the 1997 movie Titanic and has made more than 30 dives to the wreckage, spoke to CNN about the tragic outcome. Also on today's show: Espen Barth Eide, Norway's minister of climate and environment, discusses the country's bold transition to electric vehicles. To learn more about how CNN protects listener privacy, visit cnn.com/privacy