Little is known about Jacqui's life before or as the outbreak began. She cared for her brothers after their mother died; at what point in her life this was is unclear. She was living in Atlanta, where she worked for the city's zoning department. When the outbreak began, she was the only member of her family who escaped from the walkers alive. At some point, she met up with the survivor group on the outskirts of the city.
Jacqui is a survivor who left the refugee camp to gather supplies in Atlanta with Glenn Rhee, Andrea, Theodore "T-Dog" Douglas, Merle Dixon, and Morales. When the survivors were trying to figure out a way to escape the department store they were trapped in, she suggested using the building's subbasement sewer system, crediting her knowledge as a part of her former occupation working in the city zoning office. When that plan fails, Rick Grimes and Glenn attempt to grab some cars to help escape. While they make their daring attempt, Jacqui goes on the roof to watch with Andrea and Morales. When Rick and the truck arrive, she climbs aboard and escapes the undead city of Atlanta to the survivors' camp.
While Carl Grimes and Sophia Peletier are playing, they encounter a zombie eating a deer and scream, and Jacqui escorts them away as the men take care of the situation. Later, she is present for the tense conversation between Rick and Daryl Dixon, and is seen gutting squirrels as they leave for Atlanta for Merle and guns. While doing laundry at the quarry with Andrea, her sister Amy, and Carol Peletier, she and the women share what they miss most, hers being her coffee maker. When Carol's husband Ed comes around and begins snapping at the women, telling Carol it was time to go, she shouts at him that they know he beats her. After Ed smacks Carol, she watched in shock as Shane Walsh begins punching Ed senseless.
When Andrea and Amy return with fish they had caught, Jacqui smiles and hi-fives Andrea in triumph. Jacqui joins in with the conversation about Dale Horvath's watch, she says "unless I've misread the signs, the world seems to have come to an end. At least hit a speed bump for a good long while", as she is enjoying a fish feast at night with her fellow campers. The zombies attack, prompting her to flee with the others to the RV, where she is seen in the background armed with an axe, leading Carol and Sophia to Lori, Carl, and Shane, then she backed up Dale who was shooting with his rifle. She survives the attack while others are not so lucky.
As Jacqui helps in the cleanup of zombie corpses the morning after the attack, she notices blood on Jim's shirt, and demands he lifts up his shirt, but he rejects and is forced to show, revealing a bite wound. She screams out that he's been injured. She later attends the funeral for the fallen survivors and cares for Jim in the RV. She hugs goodbye Miranda Morales and her family as they announce that they are parting ways. When on the road, she cares for Jim but when the RV breaks down, she is forced to say goodbye to Jim as they leave him outside a tree on the road, since he is feeling worse. She can be seen collecting herself on the RV steps as the others say goodbye to Jim. She reaches the Center for Disease Control and is about to flee with the other survivors until the doors suddenly open.
Jacqui and the rest of her group are admitted into the CDC by Dr. Edwin Jenner after going through a blood test to ensure none of them are infected. She is introduced to the luxuries the facility has to offer, including hot water and real beds. She enjoys dinner and wine with everyone and learns about TS-19 and Dr. Jenner's work, and the fall of the CDC's infrastructure. After Dr. Jenner reveals the purpose of the countdown timer and shuts the control room's door, tears run down her face, but she manages to remain calm, while others aren't able to control themselves as well. As the survivors finally get Edwin to open the door for their escape, T-Dog grabs onto her arm, trying to pull her outside the room with him, but she pulls herself back, telling him she's staying. T-Dog tells her "That's INSANE!", attempting to pull her out with him a second time, but she once again resists, saying "No, it's completely sane, for the first time in a long time. I'm not ending up like Jim and Amy." This catches the attention of the rest of the group, as they all look back at her. Jacqui then tells T-Dog "There's no time to argue, and no point -- not if you want to get out. Just get out...get out!" she protests, then pushing T-Dog, but right after she touches T-Dog's face in a kind, motherly manner. Shane then pulls T-Dog out with the rest of the group, and Dale approaches Jacqui with a shocked look on his face. She backs away from Dale, shaking her head no, and then walks to the back of the room. She's then seen witnessing Dale pleading with Andrea to leave with him. As the rest of the group (who have managed to escape the building) are getting in their vehicles, the scene of Dale and Andrea escaping is shown on a monitor, revealing that Jacqui had ultimately decided to stay behind with Jenner, as Dale got Andrea to change her mind. Jenner says "They got out," to which Jacqui responds with a smile, happy that the people who helped her make it so far are able to continue fighting. She looks at Jenner, as they then hold onto each other's hands as the timer ticks down, and the CDC explodes. She died at peace, rather than some of her previous allies whose deaths were painful results of the walkers.
Rick begins receiving phone calls from individuals who he believes are part of another group. A woman calls Rick asking why he wouldn't reveal how Lori died to the previous man he spoke to on the phone. She calls Rick by his name, and when he questions how she knows his name, the woman says because she knows him, then hangs up the phone. Rick then receives a phone call from Lori, who informs him that the people he had spoken to previously were Amy, Jim, and Jacqui, revealing that all the calls did not actually take place in the real world, but were merely hallucinations in Rick's mind.
- Vi (Caused)
- Herself (Suicide)
With the CDC building losing power, Vi deploys the HITs to prevent any diseases from escaping and decontaminates the entire facility. Jacqui decides to commit suicide in the explosion, along with Edwin, after losing hope in things going back to the way they were.
This list shows the victims Jacqui has killed:
- Herself (Suicide)
- Possibly numerous counts of zombies
- "Hounded" (Voice Only, Hallucination)
- Jacqui states that the item she misses most is her "coffee maker with a gold drip filter and grinder".
- In a deleted scene from the Season 2 DVD, Rick blames himself for Jacqui's death, to which both Shane and Lori reply that it was her choice, that there was nothing he could have done, and that he shouldn't take that on.
- Jacqui is the last character to die in Season 1, along with Edwin.