Chongqing, a city built on mountains in Southwestern China, remains a stronghold of porters known as “bang bang” who move goods along streets on the rugged terrain. But the porters are slowly fading from view in the face of modernization. From 400,000 people working as bang bang in the city in 2010, they have shrunk to fewer than 2,000, mostly elderly. Are they really disappearing one day? Or are they simply evolving into modern-day bang bang? This film follows a few of them to see where they’re headed.