| Name | Character | Episodes |
|---|---|---|
| Stephen Graham | SIO David Kelly | 4 |
| Elizabeth Berrington | Debra Taylor | 4 |
| Jack McMullen | Dean Kelly | 4 |
| Sinéad Keenan | Melanie Jones | 4 |
| Dan Renton Skinner | DCS Brian 'Dixie' McNeill | 4 |
| Brían F. O'Byrne | Steve Jones | 4 |
| Gerard Horan | Prosecution Barrister | 4 |
| Paddy Rowan | Sean Mercer | 4 |
| Stephen Walters | DCI Mark Guinness | 4 |
| Kerrie Hayes | Sandra Oxley | 4 |
| James Nelson-Joyce | James Yates | 4 |
| Sara Powell | ACC Pat Gallan | 4 |
| Jason Thorpe | Defence Barrister | 4 |
| Nigel Betts | Tom, POLSA Officer | 4 |
| Christine Tremarco | Marie Thompson | 4 |
| Faye McKeever | Claire Olssen | 4 |
| Vanessa Emme | Police Liaison Officer | 4 |
| Jodie McNee | WDC Jackie Carter | 4 |
| Neil Fitzmaurice | Neil Jones | 4 |
| Lizzie Hopley | Marie Yates | 4 |
| Megan Dawson | Jenny Kelly | 4 |
| Alicya Eyo | Morgue Nurse | 4 |
| Michelle Butterly | Paula Kelly | 4 |
| Jay Johnson | Tony Edge | 4 |
| Andrew Schofield | Kenny Richmond | 4 |
| Rhianne Barreto | Girl | 1 |