|"Is that damage?"|
"It looks like damage."
Kelly O'Brien was a member of the United States Army and a resident of Gunnison, Colorado who, in 2004, became involved in the Xenomorph outbreak that ultimately led to the destruction of the town. Kelly had only just returned to Gunnison from an overseas tour of duty before the outbreak started.
The Xenomorph invasion
When the Predator Ship crash-lands in the small town, the Xenomorphs invade the town. Molly is using Kelly's night-vision goggles, in which she sees one of the Warrior Xenomorphs. She screams, getting Kelly & Tim's attention, saying that there was a monster outside. Tim goes to the window and is attacked by the Warrior Xenomorph. Kelly takes Molly and runs away as the Xenomorph kills Tim. Kelly & Molly retreat to a graveyard. There they encounter a man who had seen a cloaked Wolf. When Molly gets scared and the man threatens them. Wolf sees him and blasts his head off with his plasma cannon. Kelly & Molly leave, and Wolf doesn't attack them as they are unarmed. But he follows them as they enter a gun shop. Kelly & Molly meet Dallas Howard and other survivors, but the Xenomorphs have followed. Wolf captures Dallas and uses him as bait to get the Xenomorphs out in the open. Kelly throws Dallas a shotgun and but three of them to escape. Kelly and the others find an IAV Stryker and contact Colonel Stevens, who tells them to go to the center of town where there will be an air-evac to get them out. Kelly, due to her previous military past, knows that the military is trying to contain the threat. Kelly stops and only a select few leave with her to the hospital, while others continue on to the center of town. They reach the hospital which has been attacked by the Xenomorphs. Kelly and the others are able to hold them off, but two of them are killed. Kelly is able to reach the helicopter with Molly, Dallas and his younger brother Ricky. They barely escape the nuclear attack on the town.
The copter crash lands after the blast wave overtakes them. They are soon surrounded by military men and surrender their weapons. Kelly comforts Molly, telling her that the monsters are gone. She and Dallas become close because of the horrible events.
Personality and Traits
Kelly is a devoted wife and mother. She feels upset that she can't connect with her young daughter Molly. However, when the town is infested with Xenomorphs, the battle hardened soldier comes out and her protective mother instinct kicks in. When her husband is attacked, she saves Molly and leaves her husband to die (though he did tell her to do so).
She is also smart enough to know the army's true intention when they are told to wait at the town square. She knows that the army would consider containment first. Her army background also shows in her weapon skills, driving the APC and piloting the helicopter.
After they find the remains of the national guard, Kelly takes an M4A1 Carbine as a main weapon and a Beretta 92FS as a back up weapon.
- US Military personnel undergo specialized training, which leads one to conclude that she is trained as a US Armored Cavalry infantry. This means that she likely took flying lessons in her spare time. However, note that at the time of the movie, women were not allowed in combat military occupational specialties such as Armored Cav. Also, in the scene where she arrives home, she is wearing US Marine Corps desert camouflage, not Army UCP.