Amelia Pierce is an agent for the Network.
To understand how a young woman in her late 20's would become an agent it is important to know about her father. Arthur Pierce was an agent with the CIA for well over 20 years. He was a veteran field agent who had been to the hottest spots and faced death far more times that he cared to remember. He used as his cover the role of reporter for a British newspaper.
It was during a mission to pull a Soviet scientist and his ballerina daughter out of the USSR that his life took a drastic turn. He fell in love. The grown daughter, Ludi, felt the same and the two began a long intimate relationship despite rules of the Agency and the disgust of her father. After a while they married in secret and Amelia was conceived.
When Arthur's wealthy father, a former Senator, died and left a large estate to his son, Arthur was financially able to tell the Agency the truth. Instead of being fired, though, he was just pulled back to Langley where for the next ten years he was an instructor.
That long a time being out of the action chafed at him, though, for he was always one in the thick of things. Then an offer came to join the Hyatt News Service, an international news gathering outfit started by Pierce's former employer's son. A chance to at least do something other than teach made him listen to the offer and the offer was not what he expected, and it became the basis for why his daughter would later follow in his footsteps.
Numerous governments had decided, after the American Embassy in Tehran was overrun, to create a group of clandestine agents who were able to work outside the system and do things no one government would want laid at its doorstep. The cover for this group, which called itself the Network, was the Hyatt group and Pierce was being offered a chance to work for them as an agent, not just a reporter. He jumped at the chance. For the next ten years he worked for them.
Amelia knew of her father's previous profession though she was ignorant of the Network and his involvement there. She adored her father growing up and learned from him many "fun" tricks of the profession, especially during the decade he was at home every night while teaching at the Agency.
But she certainly did not intend to be a spy. She is recovering from a bad marriage and unpleasant divorce when her father is killed. In his last words he passes on an assignment to her and she finds herself learning of and becoming involved with the Network. And as a new operative, she finds herself having to use skills she hated learning from her father years before.
She also finds the excitement and purpose her life up to then has been lacking.