A power bank ignited in the overhead bin of China Eastern flight MU2421 after landing in Guiyang, sending smoke through the cabin before crew extinguished the fire on the ground. The A320, operating from Lanzhou, had already reached Guiyang Longdongbao International Airport when passengers and crew confronted the thermal event; firefighters met the aircraft and no injuries were reported. The case sharpens operator focus on lithium-ion carriage discipline, especially stowage in overhead compartments where detection and access lag. China Eastern’s rules bar power banks and spare lithium batteries from overhead bins and forbid onboard charging, aligning cabin procedures with the fire load profile of portable cells.