Throughout Who Is Erin Carter?, the titular protagonist kept getting flashes of her past life, and to put it subtly, we realized that she didn’t exactly have a white-collar job. Erin said that she was a schoolteacher, but when we saw her in the store, fighting with the robbers, we realized that she was not what she was pretending to be. It was finally in the fourth episode that the mysteries of her past life were revealed, and we got to know that she was an undercover agent working for a law enforcement agency called the CIO (Centralized Intelligence and Operations).
Erin Carter wanted to be a police officer, but after she had a fight with one of her colleagues who was trying to bully her, her application was rejected, and a disappointed Erin realized that she would never be able to bring her life back on track. But that’s when she met DI Jim Armstrong, who offered her a job, though she eventually became a bit skeptical as she realized the threats involved with the job. DI Armstrong had created a cover identity for her, given her the name Kate Jones, and got her in touch with Thomas Ramsey. Erin met both Margot Muller and Lena, who were already working for Thomas and were highly skilled assassins. Erin performed quite well in her training, and very quickly, she became an important member of the gang. Lena often brought her daughter, Harper, to the safe house, from where the gang operated. Erin intentionally made an effort to grow close to Lena and her daughter so that she could win their trust and get the information to which only the senior members of the gang were privy.
But with time, Erin started feeling genuine affection towards the mother-daughter duo, and she was scared for the day when they would get to know about her real identity. She knew they were criminals, but the way Lena put her trust in her made Erin really scared of the consequences her actions were going to have on her. They were preparing for the Harwich job when one day, two weeks before the date of the mission, Thomas came to know that the security of the place was increased for just one specific day, i.e., the day they were planning to rob the gold plates from there. Thomas realized that there was a snitch among them, and his suspicion was on the two newcomers who had recently joined the gang: Erin and a guy named Scotty.
At that moment, in Who Is Erin Carter? When it felt like Thomas would kill Erin, Lena came forward and vouched for her. Erin, too, controlled her nerves and stuck to her narrative that she was not an undercover agent. On the other hand, Scotty became all nervous, and he thought that Thomas would kill him nonetheless. His under confidence came off as a blessing in disguise for Erin, as Thomas’ men killed Scotty, believing him to be the snitch. Thomas knew that the same amount of gold plates were coming to Harwich that day also, so instead of waiting for two weeks, he improvised and told his gang that they were going to commit robbery that day itself. After the robbery, it became quite evident that it was Erin who was a police informer and not Scotty. The police force conducted a crackdown at the safe house, and Erin was able to make a near escape. Erin saw Lena getting killed in front of her eyes, so she took Harper with her because her conscience wouldn’t agree to leave the little girl behind.
But Lena had survived, and Erin had no clue that for five years, she had been rotting in prison. Lena came to Barcelona to get her daughter, and when Erin learned about it, she was not only shocked but scared because she knew what Lena was capable of. Lena was probably stuck in the most difficult situation that any mother would be in. She loved her daughter, and she could go to any extent to get her back, but Harper didn’t even recognize her. The little girl has accepted Erin as her mother so she couldn’t have the same kind of love and affection for Lena, even if she were her biological mother.
The most disheartening moment for Lena comes at the end of Who Is Erin Carter? When she reaches Olivia’s home to get her daughter. Harper stood there, unable to recognize Lena, and told her that Erin was her mother and not her. Lena asked Harper to come with her and told her to remember the times they had spent together, but the little girl went to Jordi because she was too scared of Lena. It was extremely upsetting for a mother who had fought her way through and reached there just so that she could be reunited with her daughter. But Lena had no option but to accept her fate. She was in denial for the longest time, but she knew that she wouldn’t be able to give Harper the life she deserved. Harper had made the choice to stay with Erin, even when she knew that Lena was her real mother and Lena had no option but to give in.
She knew that Harper would have a better future with Jordi and Erin, but still it was excruciatingly difficult for her to accept it as how could a mother give her daughter away and not crave to be with her? Lena always knew that she should take Harper with her, but it was not until the very last moments of Who Is Erin Carter?, she accepted that fact and made peace with it. Lena was an exceptional mother, but she was a victim of the circumstances, and now she couldn’t go back in time and change them. When Lena and Erin were getting ambushed by Daniel Lang‘s men, they realized that one of them had to give cover and sacrifice their lives so that the other could escape and save Jordi and Harper. Erin was going to go out and give cover fire when Lena stopped her. Without Harper in her life, Lena didn’t have anything to look forward to, and she made the decision that it was going to be her who was going to go out there and wreak havoc on Daniel’s men. Lena told Erin to take care of her daughter and tell her that her mother was a good person. And just like that, Lena gave her life, and it was because of her valiant effort that Jordi, Erin, and Harper were able to survive.