| Steven | Barton | A digital forensic expert. aka: Steve. |
| Maurice | Braddick | Lucy's father. |
| Lucy | Braddict | A part-time waitress. |
| Brian | Branscombe | The crime scene manager. |
| Steph | Bull | An admin. officer. |
| Jonathan | Church | Matthew's husband. |
| Wesley | Curnow | Cynthia's friend. aka: Wes. |
| John | Grieves | A tenant of Francis Ley. |
| Ratna | Joshi | A psychiatrist. |
| Francis | Ley | An economist. aka: Frank. |
| Alexander | Mackenzie | Ley's friend. aka: Mack. |
| Janey | Mackenzie | Mack's sister. |
| Peter | Mason | Francis Ley's lawyer. |
| Ross | May | A detective constable. |
| Lauren | Miller | Matthew's colleague. |
| Joe | Oldham | Matthew's boss. |
| Sally | Pengelly | A pathologist. |
| Cynthia | Prior | A magistrate. |
| Roger | Prior | Cynthia's husband. |
| Fiona | Radley | Head of the comms. |
| Jen | Rafferty | A detective sergeant. |
| Paul | Reed | A writer. |
| Viv | Reed | Paul's mother. |
| Vicki | Robb | A police constable. |
| Dorothy | Venn | Matthew's mother. |
| Matthew | Venn | A detective inspector. |
| Simon | Walden | The victim in Matthew's first North Demon murder inquiry. |
| Luke | Wallace | A boy who committed suicide in London. |
| Eve | Yeo | Nigel's daughter. aka: Evie. |
| Helen | Yeo | Eve's mother. |
| Nigel | Yeo | A medic. |
| Anthony | | Dorothy's acquaintance. |
| Ben | | Jen's son. |
| Bob | | The cafe manager. |
| Chrissie | | A missing woman with Down syndrome disease. |
| Daisy | | One of Sarah and John's daughters. |
| Ella | | Jen's daughter. |
| Finn | | One of Dr. Sally's children. |
| Freddie | | One of Dr. Sally's children. |
| George | | Mack's father. |
| Jo | | One of Dr. Sally's children. |
| Joanne | | Mel's friend. |
| Julie | | One of the employees at NDPT. |
| Lily | | One of Sarah and John's daughters. |
| Lindsay | | Owner of the Glorious Oyster resto. |
| Liz | | Wesley's mother. |
| Lizzie | | Ratna's acquaintance. |
| Martha | | Mack's mother. |
| Martin | | A financial journalist. Wesley's father. |
| Mel | | Ross May's wife. |
| Millie | | Former finance officer at NDPT. |
| Nancy | | Ley's mother. |
| Philip | | The previous boss at the NDPT. |
| Robbie | | Jen's ex-husband. |
| Sarah | | John Grieves' wife. |
| Sharon | | A police officer. |
| Tony | | One of the employees at NDPT. |
| Zach | | Ella's boy friend. |
