Sophia is an agent with the DEA who went undercover as a waitress in Miami in order to gather intelligence on a drug lord named Campos. Her cover was way too good, however, and she ended up being stalked by one of Campos' men, Raul. She hired Michael Westen through their mutual acquaintance, Sam Axe, never telling either man about her real job until Westen, suspecting that she was merely one of Campos' rivals, threatened her. Westen posed as an ally of Raul and inflitrated the cartel, then convinced Campos that Raul was plotting against him. Raul thus ran to the DEA, offering information on Campos in exchange for protection. With Campos and his cartel dismantled, Sophia has moved on to another assignment.