Brianna Dagger was an agent with the CIA.
More specifically, she is an operative in their paramilitary section which means she is not responsible for recruiting or handling foreign assets nor does anyone expert her to uncover enemy state secrets. And while she is quite intelligent, she is not asked to analyst procured data to gleam truth from it. She is sent into trouble zones with the sole purpose of ending that trouble. It might be to hunt down a traitor or help to take down a terror cell. Whenever someone or ones start being a problem, she and her partner, Max Turner, are a couple of highly dangerous agents they sent to correct that problem. It usually means physically.
Dagger, who is in her early 30s when we first meet her, works for a woman named Jane McCleary who is as hard-nosed as she can be, perpetually annoyed with the often flippant manner that both Dagger and Turner seem to approach anything - humor is not something her boss partakes in and something she does not like in her subordinates.
We learn through some side comments that Dagger was born and partially raised in Ireland in an environment that does not sound pleasant at all. At some point she was moved to the States where she apparently held dual citizenship and finished her upbringing. Along the way her father instilled in her a fascination - no, really an obsession - with parkour. Both the difficulties faced as a young child and her love of the sport are summed in the statement, "Constant awareness of her surroundings had been driven into her as a necessity before she was ten years old. When parkour was added to the picture, the awareness took on a more defined and purposeful role. She already saw paths of least resistance, paths of most resistance, and paths that appeared to be one, but were really the other."
Dagger is driven by a desire to help others, largely through stopping those hurting them. "Dagger has spent a lifetime honing her agility, and she taps her physical prowess and keen mind to overcome any obstacle to stop all enemies and save victims before it's too late." Couple that with a love of danger and we are told it was the risk that she craved the most. "It was the fact that no matter the risk, no matter the obstacle, she overcame it. Always. That's why she had joined the Agency. She faced more risk and more daunting obstacles here than in any career she could have chosen. And she overcame them every time."
As one ad hoc colleague put it, "Your boss told me you'd be hopping all over our rooftops like a jackrabbit. A bit of a march hare, are you?" Her response was, "I'm well-known for my methods, or should I say infamous." She adds after a grin, "They're effective, though".