| Maddy Griffiths | ... | Young Sam (7 episodes) |
| Jane Riley | ... | Sam's Mother (7 episodes) |
| Doc Brown | ... | Tyrone
(7 episodes) |
| Souad Faress | ... | Mrs. Sidwa (6 episodes) |
| David Sterne | ... | Dave Ryder (6 episodes) |
| Scott Handy | ... | Blank-faced man (5 episodes) |
| Indira Varma | ... | Natalie Thorpe (5 episodes) |
| Dhaffer L'Abidine | ... | Bernard Faroux
(4 episodes) |
| Aaron Neil | ... | Rahim Soomro (4 episodes) |
| Manjinder Virk | ... | Simran Bains (4 episodes) |
| Peter Vollebregt | ... | Dr. Horst Goebel (3 episodes) |
| Helen Kennedy | ... | Lianne Wells (3 episodes) |
| Jonny Phillips | ... | DI Everett (3 episodes) |
| James Daffern | ... | Andrew Hayden (3 episodes) |
| Uriel Emil | ... | Hasan Moussa (2 episodes) |
| Rob Jarvis | ... | Dr. Arthur Hill (2 episodes) |
| Sarah McCardie | ... | Scottish Woman (2 episodes) |
| Trevor White | ... | Patrik Lindberg (2 episodes) |
| Neil Finnighan | ... | Military Man (2 episodes) |
| Dermot Crowley | ... | George Ballard (2 episodes) |
| Richard Dormer | ... | Lewis Conroy (2 episodes) |
| James Hayes | ... | Priest (2 episodes) |
| Miranda Nolan | ... | Trudy Barnes (2 episodes) |
| Meera Syal | ... | Fatima Zahir (2 episodes) |
| Richard Lintern | ... | Hector Stokes (2 episodes) |
| Juliet Aubrey | ... | Orla Fante (2 episodes) |
| Maurice Lee | ... | Bodyguard (1 episode) |
| Mohamed Majd | ... | Café Khalil Owner (1 episode) |
| Colin Decker | ... | Armed Man (1 episode) |
| Cedric Proust | ... | Armed Man (1 episode) |
| Jason Hunjan | ... | Armed Man (1 episode) |
| Marene Miller | ... | Plant Inspector (1 episode) |
| Shane Salter | ... | Mall Shopper
(1 episode) |
| Elly Fairman | ... | Emma Freeman (1 episode) |
| Scarlet Margaroli | ... | Emma's Daughter (1 episode) |
| Lin Blakley | ... | Grandma Freeman (1 episode) |
| Martin Wenner | ... | Lars Holm (1 episode) |
| Jenifer Landor | ... | Polly Holm (1 episode) |
| Ben Smith | ... | Slender Man
(1 episode) |
| Jamie Kenna | ... | Security Man (1 episode) |
