Abigail Tierney, a character in The Rookie , was introduced as Henry Nolan's fiancée in earlier seasons. They eventually broke up, and Abigail pursued filmmaking, focusing on a true crime documentary about the Westview Psychiatric Hospital, a place with a dark and sinister history involving illegal government mind-control experiments

. In Season 7, Episode 15 ("A Deadly Secret"), Abigail goes missing while filming inside the abandoned Westview facility. The episode is presented as a true crime documentary and reveals that Abigail was trapped behind a walled- off section of the hospital for about two weeks. She survived on trail mix and water she had with her and made friends with the skeleton of a man named Bob, who had died months earlier

. The investigation uncovers a conspiracy involving Dr. Julius Erikson, who conducted secret mind control experiments at Westview, and Meg Davison, the hospital director who exploited wealthy patients through conservatorship schemes. Abigail was targeted for elimination by a man named Carl under Davison's orders but managed to survive until rescued by Nolan and his team

. After being found, Abigail decides to continue focusing on her documentary work, despite the trauma. Her disappearance and rescue bring personal stakes to Nolan, given her past relationship with his son Henry and her connection to the case

. In summary, Abigail was missing for two weeks inside a haunted psychiatric hospital while filming a documentary, survived against the odds, and helped expose a criminal conspiracy before being rescued