| Name | Character | Episodes |
|---|---|---|
| Saskia Reeves | Connie Petersen | 4 |
| Tom Hollander | Douglas Petersen | 4 |
| Tom Taylor | Albie Petersen | 4 |
| Iain De Caestecker | Young Douglas | 3 |
| Gina Bramhill | Young Connie | 3 |
| Sofie Gråbøl | Freja | 3 |
| Charlotte Spencer | Karen Petersen | 2 |
| Luca Matteo Zizzari | Italian police officer | 1 |
| Joe Dixon | Mike | 1 |
| Andrew Hawley | Angelo | 1 |
| Daniel Fearn | Delivery Man | 1 |
| James Doherty | Quizmaster | 1 |
| George Webster | Jake | 1 |