Eden is an empty nester and aspiring artist who recently relocated to Hope Falls, Cornwall, with her husband for a fresh start. Following her daughter's tragic accident, Eden dedicated years to caregiving, and she now hopes to reclaim her identity by launching her first art exhibition. Her life shatters when an imposter assumes her name, forcing her to flee her own home and desperately search for proof of her existence.

Olivia is a seasoned London police detective who receives a devastating terminal cancer diagnosis around her 40th birthday. Facing her mortality, she inherits a historic property called Spyglass in Hope Falls from a grandmother she never knew. Relocating to the remote village, she intends to spend her remaining time settling unfinished business, soon taking charge of a complex local missing-persons case.

Harrison is Eden's husband and the ambitious CEO of Thanatos, a company claiming to use technology to predict a person's exact date of death. He is a pragmatic, highly organized businessman who often masks his personal insecurities behind a composed, authoritative exterior. Following the bizarre incident at his home, he buries himself in his corporate work, drawing suspicion from the investigating detectives.

Carter is a 28-year-old local police officer dedicated to maintaining the idyllic, crime-free reputation of Hope Falls. While ambitious in his career, he feels trapped in a loveless marriage that he entered strictly out of obligation following an unexpected pregnancy. His procedural mindset frequently clashes with his impulsivity, especially as the lines between his professional duties and personal desires begin to blur.

Gabriella is the daughter of Harrison and Eden, currently living at a residential care facility called The Manor. Following a severe childhood accident, she lives with intellectual disabilities and selective mutism, communicating her emotions by painting different animals. She remains highly observant of the adults around her, requiring specialized care and protection.

Mary is a dedicated specialist and caregiver working at The Manor. Having recently joined the staff after her previous long-term patient passed away, she quickly forms a strong bond with Gabriella. She makes significant breakthroughs with the young woman, encouraging her to communicate through whispers and recording her progress.

Jane is Sergeant Carter's wife and the mother of their young daughter, Steren. She married Carter following a brief acquaintance, maintaining their household while mostly remaining in the background of his busy policing career. She projects the image of a steady, unthreatening wife who quietly manages their domestic life.

Maddy is Sergeant Carter's sister and a bartender at the local pub. After their parents moved to Spain, Maddy remained in Hope Falls, keeping a close eye on the village's social dynamics. She is protective of her brother and harbors a deep skepticism toward outsiders who disrupt the town's peace.

Diana is the owner of the Saltwater Gallery in Hope Falls, known locally as the "black widow" because she has outlived three husbands. She is heavily involved in the local arts scene and coordinated Eden's debut exhibition directly with Harrison. She is fiercely independent and frequently swims alone along the coastal cliffs.

Old Mrs. Bird is Olivia's recently deceased grandmother, a reclusive figure in Hope Falls known in local lore as "the woman who died twice." She lived to be nearly 100 years old in the Spyglass estate, dying peacefully alone and leaving her historic home to a granddaughter she never met.

Stu is an older resident and local dog walker who frequents the coastal paths of Hope Falls. Because he spends his days walking multiple dogs along the cliffs, he becomes a key witness in the police investigation, though his abrasive demeanor and shifting accounts frustrate the detectives.

Ingrid is a nurse working at The Manor, the residential care facility where Gabriella lives. She manages the daily protocols of the institution and communicates with patients' families, strictly enforcing the facility's rules regarding patient safety, visitation, and confinement.

Cath is a friendly waitress at a local Hope Falls café. She is observant of the town's daily rhythms and offers the investigating detectives helpful, casual information regarding the locals' movements on the morning of the incident.

Steren is the young daughter of Sergeant Carter and Jane. She serves as her father's emotional anchor, providing a source of genuine love and devotion in an otherwise complicated and unhappy household.