Abby would be your typical teenager--that is, if she wasn't part of a secret organization tasked with tracking down meta-humans. She doesn't agree with what she's doing, but when Agent Smith tells her she will be infiltrating a school to find a dangerous meta, she knows she has no choice because disobeying means that her brother will end up in their special meta-human prison.
When she meets her target, she realized that he is not as dangerous as she was led to believe. She must make the choice between saving a boy she barely knows, or turning him over to the Agency to be incarcerated. Either choice she makes, she loses.