Ping Hong is a Chinese boy who was enslaved by Wah Sing Ku and his henchmen and was going to be executed along with his family. He is later saved by Roger Murtaugh when he was discovered on a boat underneath a sheet. Ping briefly becomes a surrogate son to Martin Riggs and Lorna Cole.
Ping Hong is imprisoned on a boat along with the rest of the Hong Family and they are sent to the United States under Uncle Benny Chan's orders. But before they can reach the docks, the operation is foiled by Team Riggs/Murtaugh and the boat becomes impounded.
Ping and his family somehow made it off the boat before anyone could find them, and it isn't until Roger Murtaugh heard voices that he would be discovered on a small escape boat underneath a sheet. With the rest of the slaves being under the hands of the LAPD, Murtaugh sneakily takes Ping and the Hongs to his house without their knowledge and keeps them there until they can granted asylum.
When Wah Sing Ku and his men take the Murtaugh Family and his own family hostage, Ping somehow evades capture by hiding in the closet. After Ku leaves, Ping exits the closet and finds Riggs, Murtaugh, Cole, and everybody else tied up on the ground and the house in flames. He frees Riggs first with a pair of scissors, then gives it to him as he frees the rest. Ping leaves the house to safety as the fire department and police arrive.
He was last seen with Riggs and Lorna in Riggs' SUV Suburban at the train tracks where they're almost killed by a train by Ku's henchmen, and Riggs goes forward, thus allowing the henchmen to be on the tracks and be collided with the train. Riggs drops off Lorna and Ping with some other officers at the hideout, just before Riggs, Murtaugh, Butters, Ng, Ng's partner, and some other detectives go to the pier to meet Ku, the Triads, the General, and the Four Fathers.
Ping isn't seen for the rest of the film, but after Riggs and Murtaugh have killed Ku, they're informed by Captain Murphy that Ping and the rest of the Hongs are going to be granted asylum.