Song first encountered AvatarKorra after she had thwarted an extortion attempt by three Triple Threat Triad members, but had destroyed several private and public properties in the process. He had arrived by police airship after she had already immobilized the thugs, and was given the order by the then-Captain Saikhan to detain the triad members. However, immediately afterward, the Avatar was apprehended by Saikhan on charges of destruction of private and city property. After a short confrontation, Saikhan was knocked over by Naga, who helped Korra evade arrest, whereupon Song and the other police officers gave chase. Using several of the city's metal cables, Song rapidly gained ground on the fugitive Avatar. Using his metalbending, he was able to grab hold of her ponytail as she crossed a bridge. However, she did not stop, and bent a wall of ice behind her. Unable to release his metal cable, he crashed unabated into the wall and was knocked out, causing him to release the cable around Korra's hair.
When Chief Lin Beifong later received a tip that Hiroshi Sato had a secret Equalist factory under his mansion, she recruited Song and several other metalbending officers to search the estate along with Korra and Tenzin. After she used seismic sense to locate a secret tunnel leading to the estate's underground facilities, Lin Beifong ordered her squad to make their way down, while she instructed Mako, Bolin, and Asami to stay at the entrance, ordering Officer Song "to keep an eye on them".
After a loud noise reached the tunnel's entrance, Mako, Bolin, and Asami became worried, and the brothers decided to go after the squad. As per his orders, Song would not allow them to leave until the chief returned. Mako then distracted the metalbender with a complaint about the dust in the workshop, and began to fake a sneeze, eventually sending a breath of fire at him. Song was forced to move backwards, and he tripped over a rock created by Bolin's earthbending. The earthbender then bound the officer to a large metal container and Mako apologized, understanding that Song was just doing his job. Bolin then repeated Song's orders to him, telling him "Just stay put until the chief comes back."
Due to this, however, Song evaded the fate of the other police officers who were captured during the following underground battle. He was released shortly afterwards and escaped from the Sato estate together with his wounded Chief, Tenzin, Korra, Mako, Bolin and Asami.
Later on, after Chief Beifong's resignation, Saikhan was appointed Chief of Police. During a speech outside of the police headquarters, Song acted as his personal bodyguard together with several other officers.
Song was also present when the new law that forced non-benders to obey a curfew was enforced by the Republic City Police with violence at the Dragon Flats borough. Acting under Tarrlok's command, he aided the mass-arrest of innocent non-bending protesters who were supposed to be Equalists. He also helped to arrest several members of Team Avatar.
After the abduction of the Avatar, Song arrived at City Hall along with his Chief and many other officers to gather evidence. When Councilman Tenzin arrived and confronted Tarrlok about Korra's whereabouts, Song stood at the front door of the Council room to prevent unauthorized access.
During the Equalist bombing of Republic City, Song was in the communications room at the police headquarters helping his Chief, who attempted to coordinate the city's defenses. However, the Equalists soon flooded the headquarters with gas, attempting to knock everyone inside unconscious. Tenzin, who had arrived just moments before the attack, led Song and his fellow policemen to safety using airbending to make a pocket of breathable air. When they reached the exit, several mecha tanks were waiting for them. Using a large magnet mounted on an arm of the mecha tanks, the Equalists captured Song, Saikhan, and the third metalbending officer. Song was then placed in a truck to be taken to Amon along with Saikhan and the other officer.
Song proved several times to be an extremely loyal and dutiful police officer who never questions his superiors. Even when Councilman Tarrlok ordered the police force to arrest innocent non-benders, Song followed the command without hesitation, proving his extreme loyalty to the police. However, he reacts to criminal or disrespectful behavior with anger, evidenced by his outraged attitude toward Korra's attempt to escape the police by knocking Captain Saikhan over.
However, he quickly becomes uncertain in unexpected situations. For example, Song panicked when Korra bent a wall of ice to stop him and he was completely overwhelmed by Mako's sneezing trick.