Lindsey is a 30-year-old hotel manager living at home with her parents in Mt. Randall, North Carolina. Her life has been entirely defined by the disappearance of her older sister 24 years ago. She struggles to establish an independent identity outside the shadow of this family tragedy and decides to search for the truth when the cold case gains renewed attention. Her investigation brings her into contact with a visiting journalist, sparking both curiosity and caution.

Jessica is a former high-achieving student whose mysterious disappearance in 1998 sparked a decades-long cold case. During her freshman year at Southern State University, she joins the Pi Gamma Delta sorority and begins dating a charismatic student. She soon struggles with declining grades and emotional turmoil. The narrative alternates to show her life unraveling in the months leading up to her vanishing.

Ben is the father of Lindsey and Jessica. Working as a successful real estate broker, he shares an unusually close bond with his older daughter. He is deeply protective of his family and displays intense frustration with the local police department's handling of the long-stagnant investigation. He frequently retreats to the family garage to spend time with his prized 1965 Boss 429 Mustang.

Ryan is a journalist from the Chicago Courier who travels to Mt. Randall to write a story about the missing college students. He possesses a quick temper and harbors a deep personal investment in the cold case, deliberately seeking out Lindsey at the hotel to gain access to the family's perspective. In the 1998 timeline, he appears as a charming college student who pursues a relationship with Jessica.

Cara is the mother of Lindsey and Jessica. Trapped in a state of suspended mourning, she copes with her grief through denial and an overprotective attachment to her surviving daughter. She struggles to maintain the appearance of a normal, happy family despite the emotional distance between her and her husband.

Daisy is Jessica's sociable college roommate from Dallas. She frequently clashes with dormitory authorities over broken rules but grows increasingly concerned by Jessica's erratic behavior as the semester progresses. In the present day, she works as a campus counselor dedicated to protecting students from exploitation.

Dr. Daniels is a respected statistics professor at Southern State University. He maintains a pristine public reputation protected by the administration, though rumors circulate among the student body regarding his inappropriate relationships with young women in his classes.

Sergeant O'Neil is the original lead detective on the 1998 missing persons cases. Initially treating the disappearances as voluntary runaways, his investigation is marked by a reluctance to challenge the university's powerful reputation. Now elderly and retired, he holds the original case files in his home.

Lieutenant Higgins is the modern-day detective assigned to reopen the cold cases after heavy rains expose remains near Doll's Eye Lake. Thorough and methodical, she utilizes contemporary forensic technology to uncover connections that the original investigators missed.

Tammy is a strict resident advisor at Westwood dormitory with a 3.9 GPA and a passion for jam bands like Phish. She is the first Southern State University student to mysteriously disappear in November 1998, though authorities initially dismiss her absence as a voluntary trip to a concert.

Phoebe is a shy, studious pledge sister in the Pi Gamma Delta sorority. She becomes the second young woman to vanish from the university campus, prompting the police to finally open a formal investigation into the missing students.

Meghan is a college freshman at Southern State University. She is the final student to go missing during the 1998-1999 academic year, further escalating the panic surrounding the campus.

Stella is the British co-host of a popular transatlantic true crime podcast called Ten Seconds to Vanish. Her cheerful, entertainment-focused approach to the Mt. Randall tragedy often conflicts with the real pain experienced by the victims' families.

Rachel is the American co-host of the true crime podcast investigating Jessica's case. Alongside her partner, she speculates on suspects and dissects the town's history for an eager online audience, increasing public pressure on the real police investigation.