Stalin's Secret Lair

S2, E11: Moscow is a city known for its ruthless leaders and abundant secrets. Today it's a modern metropolis, but far below its crowded streets lie the reminders of its war-torn past, and pieces of Stalin's terrifying legacy. This subterranean web is so vast, modern day Moscow is actually in danger of caving in. From tunnels used to hide from Stalin's blood-thirsty henchmen, to secret metro systems and hidden bunkers, Don digs deep into Moscow's past.