| | | | Summer 2003 |
| | Thea | | Murdered. |
| | Ollie | | Thea's friend. |
| | | | Thursday 10:00 AM 2021 |
| | Larson | Creacher | The island caretaker in 2003. The suspect on the 2003 killing spree. |
| | | | Reaper's Rock - The strange island. |
| | | | Day 1 |
| 1 | Elin | Warner | A former agent of crime investigation unit. A detective sergeant. |
| | Isaac | Warner | Elin's brother. |
| | Steed | | A detective constable. Elin's colleague. |
| | Anna | | The HR. Elin's boss. |
| | Will | Riley | Elin's boyfriend. The founder of LUMEN. |
| | | | LUMEN - The luxury retreat on the island. |
| 2 | Hana | Leger | Jo's sister. One of the island visitors. |
| | Jo | Leger | Hana's sister. One of the island visitors. |
| | Bea | Leger | Hana and Jo's older sister. |
| | Liam | | Hana's dead boyfriend. |
| | Maya | | Hana and Jo's cousin. |
| | Seth | Delaney | Jo's boyfriend. |
| | Caleb | | Bea's boyfriend. |
| 3 | Hayler | | Murderer of Elin's brother's
fiancé. |
| | Sam | | Elin's sister. Deceased. |
| 4 | Edd | | Jo's driver. |
| 5 | Sofia | | Maya's younger sister. |
| 6 | Farrah | Riley | Will's younger sister. The Lumen manager. |
| | Tobias | | Farrah's ex-boyfriend. |
| | | | Day 2 |
| 10 | Michael | Zimmerman | The cleaner of the pavilion. |
| 12 | Leon | | A CSI agent. Elin's colleague. |
| | Rachel | | Leon's partner. |
| 13 | Jon | | The medic. |
| 17 | Justin | | The Lumen's security guy. |
| 19 | Della | | Bea's assistant. |
| 21 | Tom | | The water sports instructor. |
| | | | Day 3 |
| 32 | Rob | Tooley | The missing guest. |
| 36 | Ronan | Delaney | Seth's father. The island owner. |
| 40 | Porter | Jackson | The island's local resident. The boatman. |
| 45 | Sol | | Maya's ex. |
| 47 | Mieke | | One of the forensic pathologists. |
| 55 | DS | Johnson | The detective in charge in Creacher murders. |
| 60 | Lois | Wade | Missing. |
| 68 | Josh | | Will's friend. |
| | David | | Will's friend. |
| 70 | Jared | | The Lumen's supervisor. |
| 77 | Alain | Dunne | The former student at Rock House School. |
| | | | Day 4 |
| 86 | Christopher | Jackson | Porter's alleged son. |
