Sonja Percy is a former agent with the ATF- Alcohol, Tobacco and Firearms, often working undercover in various lone operations.
In September 2015, upon becoming an official NCIS Special Agent, she was assigned to the NCIS: New Orleans office led by NCIS Special Agent in Charge Dwayne Cassius Pride and for three years, Sonja worked as an NCIS agent before she resigned from NCIS in April 2018 to join the FBI or Federal Bureau of Investigation as a Special Agent.