On March 8, 2014, Malaysian Airlines Flight 370, and its 239 occupants, took off from Kuala Lumpur International Airport with a final destination of Beijing, a journey that should have been no more than seven hours long. Not only did the Boeing 777 never make it to China, it hasn’t been seen since, and all its passengers and crew members are presumed to have died somewhere in the Southern Indian Ocean.

What sounds like an episode of "Unsolved Mysteries" is the subject of a new Netflix documentary titled "MH370: The Plane That Disappeared," which chronicles the mysterious vanishing of a commercial jet, the years-long investigation into its disappearance, and the various theories avionics experts and the families of the missing passengers have come up with in the nearly 10 years since the fateful flight.

Here are five things you should know, if you have not watched the most perplexing Netflix documentary.