| Mary | |
| Age | Unknown |
| Born | The Fringe |
| Gender | Female |
| Height | Tall |
| Hair | Red |
| Allies | Tobias Eaton Rafi Reggie Nita |
| Enemies | David |
| Fate | Alive |
| Appearances | Allegiant |
Mary is a strong, tall, red headed girl. She worked with Juanita "Nita", Reggie, Rafi and Tobias Eaton to attack David by explosions and shooting guns. They threatened to kill David if he didn't open the door to the Weapons Lab where they seek the Death Serum AKA Erudite Serum.
Until Tris Prior and Matthew interrupted their crimes against David, she shot Nita and saved David just to become his best friend and get information out of him. Except for Mary, she was arrested, along with Tobias Eaton, Nita, and Rafi.