This week's episode takes us back to 24 March 2015. On this day, Germanwings flight 9525 took off from Barcelona Airport with 144 passengers on board, together with four crew and two pilots, bound for Dusseldorf. Half an hour in to the flight, Captain Patrick Sondenheimer left the cockpit to go to the bathroom. His co-pilot, First Officer Andreas Lubitz, locked the cockpit door from the inside, before plunging the plane in to a terrifying ten minute descent. As the plane hurtled towards the ground at 440mph, Captain Sondenheimer screamed at Lubitz to let him back in to the cockpit. When his demands went unanswered, he attacked the cockpit door with an axe in front of screaming passengers, but it was all in vain. Before he could regain control of the plane, Lubitz smashed it in to the side of a mountain, deep in the French Alps, killing everyone on board.