Tara was once a nanny in Los Angeles, hired by the Perez family to watch over the son Jake. One day, on May 9, 2010, she and Jake were lured in and abducted by a man named Johnny Ray Covey, who also abducted a nearby woman vacationing from Dallas, Texas, named Allison Astor, presumably because she saw Tara's abduction and tried to intervene. Johnny spent the next two days torturing and raping Tara and Allison, while he released Jake unharmed. On the second day of her captivity, Tara managed to escape, possibly because Johnny couldn't keep an eye on two victims at once. She had an opportunity to free Allison and bring her along, but Tara fled without her out of fear. Tara was found by a garbage truck driver passed out in an alleyway in the Hollywood district, with no memory of who took her or where she was held, having dissociated from the event.
JJ and Morgan, investigating Johnny's killings with the rest of the BAU at the time, questioned her repeatedly and even tried to do a cognitive interview, but they were unable to get any results since she was too traumatized by her abduction. For the next three years, Tara was contacted by the BAU, who were trying to get more information, but she refused to speak to them any further. At some point, she moved to Seattle, Washington, where she got a job as a waitress, and started seeing a psychiatrist, Doctor Jerry Berneman. At the time, she was officially diagnosed as having PTSD and insomnia, as well as occasionally having suicidal tendencies. Tara eventually developed a habit of snapping her wristband as a form of aversion therapy, whenever she is exposed to external stimuli triggering her memories. However, by the events of Nanny Dearest, she was starting to move on from the trauma of the event, even recently having a date.
In 2013, Johnny abducts another nanny and child, Gina Mendes and Phoebe Payton. Realizing this, JJ and Morgan head off to Seattle to interrogate Tara. When they find her at her workplace, she initially tries to send them away and tries redirecting them to Berneman, but they insist and she eventually caves in. At another table, JJ and Morgan assure her that her memories are not lost but locked away, and also tell her about the serious situation Gina and the asthmatic Phoebe are in. At the same time, Tara overhears a baby crying, which starts to bring back memories of her abduction. As a result, she loses focus and starts snapping at her wristband. JJ manages to regain her attention, but when she urges her to help them, Tara is overcome with fear and refuses to divulge any more information. She quickly leaves, dismaying JJ and Morgan. As a result, the two agents contact Berneman, who tells them about Tara's experiences in therapy and advises them to give her some space. When the BAU deduce that the unsub had seen something special in Gina and Phoebe, they hold a press conference, where they release their profile of Johnny before allowing Phoebe's parents, Shane and Melody, to speak.
Tara sees the conference, has a change of heart, and allows JJ and Morgan to interview her. During an interrogation process referred to as EMDR (eye-movement desensitization and reprocessing), they use a blinking device to provoke Tara's mind into uncovering hidden pieces of information. It is partially successful, as Tara is able to recall Allison before she caves in under the pressure and flees from the room. JJ convinces her to continue; and Tara is able to inform the BAU of how she escaped, Allison's physical description, and the fact that her abductor has a dog. With Garcia's help, the team traces down Allison's body, and the coroner holding it tells them that Allison had been bitten savagely by a dog; this gives the BAU the leeway to narrow down their list of possible suspects. Eventually, the BAU is able to find Johnny, kill him, and rescue both Gina and Phoebe. The following night, as Shane and Melody reunite with Gina and Phoebe, JJ congratulates Tara for helping to save two lives, then allows her to view Johnny's corpse in contempt. Melody spots Tara and hugs her, thanking her for her assistance.